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and about seven inches long, doubtless near its full length, for grown ones, taken alive out of the belly of a boa, varied from eight to ten inches.

Mr. Gosse says:-"The interest ing circumstance of the Python bivitatus incubating its eggs, which took place in the menagerie of the Museum of Paris, is thus shown to be characteristic of the family, the habit being common to the American and Indian species of the Boada; for the fact that the foetus in the case which I have recorded above was fully formed and capable of motion when extracted, sufficiently proves that some time had elapsed since the deposition of the eggs, while the exit of the boa from the nest, which led to the discovery, shows that the parent was still fulfilling the duties of incubation." "The generation of the Boada is well known to be oviparous." Notwithstanding that, he says:"Other persons have assured me that often on killing a female yellow snake (the boa) they find the young in her belly. And this is curiously confirmed by a note from Mr. Hill, who thus writes me :-"The Honour able Thomas James Bernard, member of the Council, has related to me a very curious fact of the yellow snake. Lately his labourers in the Pedro mountain district, St. Ann's, killed a yellow snake containing some ten or twelve grown young ones varying from eight to ten inches in length. The Negroes expressed their surprise at this circumstance, because they knew that this boa produced its young from eggs.' A phenomenon like this was well calculated to call forth from Negroes their usual "golly golly" of surprise, but it should have excited in intelligent observers and professional naturalists some other idea than that snakes have a "local option" in bringing forth their young, by eggs hatched in the ground, or by incubation, or by

"bearing them alive." Mr. Hill timidly ventures the remark : -“ Is this to be received as a case of snakes that retire upon alarm into the mouth and stomach of the parent? It is stated of the rattlesnake in 'Hunter's Memoirs of a Captivity Among the North American Indians,' that, when alarmed, the young ones, which are generally eight or ten in number, retreat into the mouth of the parent, and reappear on its giving a contractile muscular token that the danger is past.' Credible eye-witnesses say the same of the European viper. (See Charlesworth's Mag. Nat. His., Vol. I., new series, 1837, p. 441.)"

Notwithstanding what has been said of the boa being oviparous and an incubator, Mr. Gosse, at pages 323 and 501, says that Mr. Hill describes her as viviparous, on the authority of "a young friend studious of natural history," who wrote him thus:-"It was on the 3rd of July, 1849, that I caught the snake [a gravid boa]. I put

it into a box with a wire front. I could never induce the snake to eat, though I offered it everything I could think of; and it was more savage than most others, and bit me several times, each bite drawing blood, like a severe scratch from a cat. It measured 6ft. 1in. (its tail short and blunt), and 10in. round the body. It was very inactive, lying all day in a corner of its cage, or coiling in graceful folds about the perches. On the morning of the 19th of October I was surprised to find my captive had produced twenty-three young ones; they were all perfectly formed, and of much the same size. I measured six of those that died first, and found them 16 in. long, and 11⁄2 in. in circumference. The last of the young ones died on the 24th, and the mother on the 28th of the same month. I am anxious to try them again, for I always sup

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posed they laid eggs, like other | ones, each 16 inches, would give
snakes, though this one certainly 368 inches of snake, which would
brought forth her young alive.-F. doubtless make the mother thicker
R. Griffith, Cumberland Pen, Ja- than ten and a half inches round
maica, 8th May, 1851."
the body, in her most bloated
condition, as to which Mr. Griffith
says nothing. If his snake had
been killed when captured, the
young would doubtless have been
found inside of her, of about half
their size when seen by him, like
those taken out of other snakes
running at large. And this would
have made the following remark of
Mr. Gosse unnecessary :-"Is it
possible that a serpent nominally
oviparous might retain the eggs
within the oviduct until the birth
of the young when circumstances
were not propitious for their deposi-
tion?" That at least is not proba-

We have here no evidence what-
ever that these snakes were there
and then "brought forth alive."
The language used would not
necessarily imply that this snake
produced young from a womb, like
mammals (which no snake does),
but merely that she did not lay
eggs. If they were hatched inside,
what had become of the shells of
the eggs? These could not have
been missed, and as Mr. Griffith
says nothing about them we must
conclude that the young were not
then born at all, but let out of the
mouth, having been hatched by in-
cubation and swallowed before cap-ble.
ture, and let out at night or during
the day when all was quiet, and
quickly swallowed on the approach
of any one, without being noticed,
till nature could hold out no longer,
when they were let out for good,
leading perhaps, directly or indi-
rectly, to the death of both mother
and young. This boa must have
had her young long before the 19th
of October, perhaps before the
19th of July, like snakes in
America, those as far South as
Louisiana being hatched not later
than the 1st of August. How did
it happen that these snakes, pro-
duced by a small one six feet one
inch, were 16 inches long, when
others often taken alive out of other
snakes (we will assume of the same
length) were only from 8 to
inches-about half the size of Mr.
Griffith's? And how did it happen
that eggs 1 inch by inch, like
those examined by Mr. Gosse,
yielded snakes 16 inches by

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inch, as found by Mr. Griffith?
That is, how could these be eleven
times the length and fully the width
of the eggs from which they had
just emerged? The mother was
73 inches long, and the 23 young

It would certainly be interesting to confine snakes pregnant with eggs, with no means of depositing. them, to be hatched by the soil or by incubation, and carefully watch results; but it would be necessary to know that they were really pregnant with eggs, which would be a difficult, if not impossible, matter to do; so that the only principle to guide the person making the experiment would be to find the shells of the eggs along with the young as they made their appearance, to feel sure that the mother contained eggs to begin with. Mr. Gosse is right when he says:—“ If there was no error in the observation of this case, it must be considered as an aberration of habit;" but very wrong when he adds, in the appendix, that, "Mr. Hill obtained from his informant the following clear and interesting details of the matter which render the fact [of the yellow boa being viviparous] indubitable, however strange," for, as I have said before, he presented no evidence whatever that the snakes were born there at all.

If people in Jamaica will make. experiments they will doubtless

find that the yellow boa, like many | circumstantial, exact and logical, in other serpents, is a "swallower;" his information, to make it of any but they should bear in mind that use in settling a question like the a naturalist cannot be too full and one under consideration.

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AMERICAN SNAKES.*

that he has seen the act, and believes with us. I will return your papers at an early date."

ROFESSOR G. BROWN | Sheffield Scientific School, Yale GOODE, of the University of College, assures me Middletown, Connecticut, caused a notice to appear in an Agricultural Paper, having a wide circulation in the United States, asking for information on the subject of snakes swallowing their young. I have a letter from him, dated "Headquarters U. S. Fish Commission, Peak's Island, Portland, Maine, July 21st, 1873," in which he says: I have in my possession over fifty letters from all parts of the United States giving the testimony of persons who have not only found the young in the throat of the parent, but have seen them run into her mouth. I am not getting up a formal discussion of the subject, but am thinking of reading a short paper at the meeting of the American Association, next month. I find that many of our naturalists seem determined not to believe in it, yet I cannot but think that the evidence sustains our side. May I use your name, if necessary, in connection with this question? Professor Sydney J. Smith, of the

It has often occurred to me that the female snake must have two throats-one for ordinary purposes and the other to give a passage to her young, or one throat for a certain length, leading by a valve, as it were, to another that enters the chamber that contained the eggs, and which doubtless becomes the receptacle of the young when hatched. It will be difficult to find this passage unless when it is in use, for it will become so contracted at other times as to escape any observation that is not very minutely made. Mr. Goode speaks of the young being found in the throat of the parent, which is evidently a slip in a hasty note, for it is in the body they take refuge― apparently in the chamber that contained the eggs, which, as I said on a former occasion, appears to be distinct from the stomach proper.

AME

AMERICAN SCIENCE CONVENTION ON SNAKES.‡

ON

N the 23d July I informed you swallow their young. The followthat Mr. G. Brown Goode, ofing is an abstract of a paper read Middletown University, Connecticut, had received many letters from different parts of the United States, testifying to the fact that snakes

* Dated July 23d, 1873.

This notice appeared on February 1st, 1873.

Dated September 10th, 1873.

by him before the Science Conven- | tion at Portland, in the State of Maine, as taken from the New York Tribune, of the 27th of August:

66 ON

THE QUESTION DO SNAKES SWALLOW THEIR YOUNG?' BY G.

BROWN GOODE, OF MIDDLETOWN

UNIVERSITY, CONN.

"This paper discussed the habit observed in certain snakes of allowing their young a temporary refuge in their throats, whence they emerge when danger is past. He stated that the question had been a mooted one since the habit was first discussed by Gilbert White in his Natural History of Selborne,' published in 1789. Reference was made to the views of Sir William Jardine, M. C. Cooke, and Prof. F. W. Putnam, as well as to the recent discussion of the subject in The London Land and Water.

"The question can only be decided by the testimonies of eye-witnesses. Through the courtesy of the editors of The American Agriculturist, a note was inserted asking for observations. By this means and by personal inquiry the testimony of 96 persons has been secured. Of these, 56 saw the young enter the parent's mouth, in 19 cases the parent warning them by a loud whistle. Two were considerate enough to wait and see the young appear when danger seemed to be past, one repairing to the same spot and witnessing the same act on several successive days. Four saw the young rush out when the parent was struck; 18 saw the young shaken out by dogs, or running from the mouth of their dead parent; 29 who saw the young enter, killed the mother and found them living within, while only 13 allowed the poor parent to escape; 27 saw the young living within the parent, but as they did not see them enter, the testimony is at least dubious.

"It may be objected that these are the testimonies of laymen, untrained and unaccustomed to observation. The letters are, however, from a very intelligent class of farmers, planters, and business men-intelligent readers of an agricultural magazine. In addition, we have the testimony of several gentlemen whose word would not be doubted on other questions in zoology. There were given the statements of Prof. S. J. Smith, of Yale College, Dr. Edward

Palmer, of the Smithsonian Institution, the Rev. C. L. Loomis, M.D., of Middletown, Conn., and others; and the gist regarding the Scaly Lizard of Europe (Zootoca vivipara), which has a similar habit.

statement of the editor of The Zoolo

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In the opinion of Profs. Wyman and Gill and other physiologists, there is no physical reason why the young snakes may not remain a considerable time in the dilatable throat and stomach of the mother. The gastric juice acts very feebly upon living tissues, and it is almost impossible to smother reptiles. Toads and frogs often escape unharmed from the stomachs of snakes. If the habit is not protective, if the young cannot escape from their hiding-place, this habit is without parallel; if it is protective, a similar habit is seen in South American fishes of the genera Arius Bagrus and Geophagus, where the males carry the eggs for safety in their mouths and gill-openings.

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Since many important facts in biology are accepted on the statements of a single observer, it is claimed that these testimonies are sufficient to set this matter forever at rest. The well attested cases relate to the garter snake and ribbon snake (Eutœnia sirtalis and saurita), the water-snake (Tropidonotus sipedon), the rattlesnake (Caudisona horrida), the copperhead and moccasin (Ancistrodon contortrix and piscivo rus), the massasauga (Crotalus tergeminus), the English viper (Pelias berus), and the mountain black-snake (Coluber Alleghaniensis). It is probable that the habit extends through all the species of the genera represented, as well as throughout the family of Crotalida. It is noteworthy that all these snakes are known to be ovoviviparous, while no well attested case occurs among the truly oviparous, milk snakes (Ophebolus), grass snakes (Liopeltis and Cyclophis), ground snakes (Storeria), or smooth black-snakes (Bascanion constrictor). It yet remains to be shown that the habit is shared by egg-laying snakes. Further observations are much needed, as the breeding habits of more than 25 North American genera are entirely unknown.

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"Prof. Gill corroborated the statement that there was no physical reason why the habit could not exist, and said that he considered the evidence sufficient to finally decide the matter. He repudiated the popular idea that snakes

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it down as an axiom that we must
hold that all snakes swallow their
till the opposite can be
young
proved of any particular species of
them.' In this paper allusion is
made to the gastric juice of the
mother. On the occasion men-
tioned, I said I was under the im-
pression that she must have two
throats, or one with two passages,
one passage leading to the stomach
proper, and the other to the cham-
ber that contains the eggs, apparent-
ly where the young ones take
refuge. We are also told that
"twenty-seven [people] saw the
young living within the parent, but
as they did not see them enter, the
testimony [as to their having been
swallowed] is at least dubious."
How could that be doubted if the
young were hatched from eggs de-
posited in the ground? And if the
species were viviparous, how could a
chain of eggs, in twenty-seven in-
stances, change into a stomach full
of young, with no remains of the
shells of the eggs from which they
were hatched, in the face of so
many such serpents having been
actually seen to swallow their young,
to say nothing of the uncertainty
of how or where the eggs were
hatched? It would be interesting to
know on what authority so many
kinds of snakes are classed as vivi-
parous. If it is merely because they
have been killed with young inside
of them, the evidence would not
hold good in the face of their swal-

In this abstract allowance must be made for incorrectness or incompleteness in reporting; still I may make a few remarks on some points contained in it. I said, on a former occasion, that a string of eggs lying along the back of a black-snake appeared to be contained in a roomy chamber distinct from the stomach proper. The young I took out of a garter snake were not lying in a string, like these eggs, but filled up about the middle third of the body, about equally distant from the head and tail-not mixed up in any way with the entrails, but presenting somewhat the appearance of a nest or bag-full of caterpillars found on a tree; if we imagine it of an elongated shape, and the larvæ lying in more than one length longwise. Both the black and garter snakes are beyond question egg-laying or oviparous, and "swallowers," for their eggs have been found in the ground in all stages of maturity, and the young have been seen running into and been taken out of the mother, as I have on more than one occasion mentioned. It thus seems odd to be told in the abstract that "all these snakes [in-lowing their young. I know no cluding the garter one] are known to be ovoviviparous, while no well attested case [of swallowing] occurs among the truly oviparous;" and that "it yet remains to be shown that the habit is shared by egg-laying snakes.' There is some confusion in the paper itself, or in the abstract made of it, on that head. The real value of it is that it proves that "many kinds of snakes swallow their young," and bears out what I said on a former occasion:-" I lay

way to determine the fact but by taking the eggs out of the snake and examining their condition; and then there would be the question whether the eggs are hatched inside or outside of the mother, or in the act of parturition. As in mathematics we require to know some things to demonstrate others, so in snakes swallowing their young, it is not necessary for a man

*See page 29.

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