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and Phyllodactylus. The Allnand and Belly collection comprise 33 Reptiles and 16 Batrachians. Among the latter are 2 new species of Mantidactylus and i of Stumpffia. There are but 11 Sphidia, but these include types of two new genera, Compsophis and Alluondina and a new species of Pseudoxyrhopus. The Lacertilia, 22 in number, yield 4 new species referred to the following genera: Chameleon, Brookesia, Uroplates and Paracontias. The diagnosis of the new Reptiles of this collection have been previously given in the Comptes rendus de la Soc. Philom. for 1894.

A comparison of these two collections, with the forms described by Prof. Boettger from Madagascar, shows that certain species considered by him as peculiar to Nossi-Bé are found distributed all through the northern part of the island. This is true not only of the Reptiles but of the Batrachians also. (Bull. Soc. Philom., Paris, 1895.)

The Molting of Birds. In a paper published recently in the Proceeds. Phila. Acad., Mr. Witmer Stone gives a detailed account of his observations on the molting of birds, with especial reference to the plumages of the smaller land birds of eastern North America. Attention is directed to the following points: order, number and times of molt; change of color by abrasion; seasonal plumages; direct change of color in feathers. As a result of his studies Mr. Stone makes the following generalizations:

I. The annual moult at the close of the breeding season is a physiological necessity, and is common to all birds.

II. The spring molt and striking changes of plumage effected by abrasion are not physiological necessities, and their extent is dependent upon the height of development of coloration in the adult plumage, and does not necessarily have any relation to the systematic relationships of the species.

It naturally follows that closely related species may differ materially in the number and extent of their molts, and that males and females of the same species differ greatly in this respect when the nuptual plumage of the adult male is highly developed as compared with that of the female or with its own winter plumage.

III. The amount of change effected in the plumage at any particular molt varies considerably in different individuals of the same species and sex.

IV. Some species which have a well marked spring molt in their first and second years may discontinue it afterwards, when the adult plumage has once been acquired. And, on the other hand, some indi

viduals may continue to molt in the spring, while others of the same species cease to do so.

V. The remiges are molted less frequently than any other part of the plumage. As a rule, they are only renewed at the annual molt (exception Dolichonyx).

VI. Variability in the order of molt in the remiges and presence or absence of molt in the flight feathers at the end of the first summer are generally family characters, i. e., Ceryle differs from any other species treated of in this paper in the order of molt in the primaries. All Picidæ and all Icterida, except Icterus (and Dolichonyx ?), molt the flight feathers with the rest of the first plumage. None of the Oscines except Icteridae (as above), some (all?) Hirundinidæ, Olocoris and Cardinalis molt the flight feathers at this time.

Mr. Stone's conclusions as to “color-change without moulting" are the same as those reached by Chapman, in his article on "The Changes of Plumage in the Dunlin and Sanderling," namely: that color-change without molt or abrasion is incapable of taking place from the very nature of the structure of a feather, and that all the cases so reported can be otherwise accounted for. (Proceeds. Acad. Nat. Sciences,

Phila., 1896.)

The Florida Deer.-The fact that the Florida deer is but little more than half the size of the deer of northeastern United States, together with certain cranial and dental peculiarities, is sufficient, according to Mr. Outram Bangs, to give it full specific rank. He therefore describes it under the name Cariacus osceola. The most striking differences between the Florida animal and its northern relatives are (1) the shape and size of the nasal and maxillary bones, and (2) the very large molar and premolar teeth. (Proceeds. Biol. Soc. Washington, Vol. X, 1896.)

ENTOMOLOGY.'

Professor Forbes' Eighth Report.-The nineteenth report from the office of the State Entomologist of Illinois, covering the years 1893-4, has recently been issued. It is the eight report of the present incumbent, Professor S. A. Forbes, and adheres closely to the lines of thorough and accurate record, which have made its seven predecessors notable in the literature of economic entomology. The bulk

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Edited by Clarence M. Weed, New Hampshire College, Durham, N. H.

of the volume (189 pages) is devoted to the Chinch Bug-the archenemy of Illinois agriculture, a voluminous record being made of the experiments with contagious diseases carried on by the entomologist and his assistants. There is also an article on the White Ant in Illinois, and in an appendix of 65 pages Mr. W. G. Johnson, assistant entomologist, gives an excellent discussion of the Mediterranean Flour Moth.

Flies Riding on Beetle's Back.-Rev. A. E. Eaton, the wellknown British entomologist, writing from Bône, Algeria, sends this interesting note to the Entomologist's Monthly Magazine: "Across the mouth of the Seybouse, on sandy pasture land bordering the seashore, big coprophagous beetles are common, sheltering in large holes in the soil when at rest, and running about on business. A small species of Borborina may often be seen riding on their backs, chiefly on the pronotum, and about the bases of the elytra-sometimes half a dozen females on one beetle. The beetles occasionally throw themselves on their backs to try and get rid of them by rolling; but the flies elude all their efforts to dislodge them, dodging out of harm's way into the joinings of the thorax and out again, and darting from back to breast and back again, in a way that drives the beetle nearly mad. In vain she scrapes over them with her legs; in vain does she roll over or delve down amongst the roots of the herbage; the flies are as active as monkeys, and there is no shaking them off. It is difficult to get them off into the killing bottle; nothing persuades them to fly; and they would very much rather stick to the beetle than be driven off it down into the tube."

Proteid Digesting Saliva in Insect Larvæ.-Dr. Wilibald Nagel describes the method of feeding in larvæ of Dytiscus. In these larvæ the mouth is very much reduced in size, and the ingestion of food is performed by means of suction through the much modified mandibles, the process being facilitated by the powerful digestive action of the saliva. Under natural conditions the larvæ eat only living animals, but in captivity they will also take pieces of meat. The saliva has a marked poisonous action, killing other insects, and even tadpoles of twice the size of attacking larvæ, very rapidly. The larvæ not only suck the blood of their victims, but absorb the proteid substances. Drops of salivary juice seem to paralize the victim and to ferment the proteids. The secretion is neutral, the digestion tryptic. Similar extra-oral digestion seems to occur in larvæ of ant-lions, etc., and 2 Biol. Centralbl., XVI, 1896, 51-57, 103-112.

spiders, and according to Krause, in Cephalopods.-Journ. Royal Micros. Society.

Weismann on Dimorphism in Butterflies.-For some time The Entomologist has been publishing a series of interesting articles by Dr. August Weismann on the Seasonal Dimorphism of Lepidoptera. The June number contains a recapitulation from which we take this extract: "Although I am far from considering the few experiments, which I could here put forward, as sufficient for reaching a decisive settlement of our opinions on seasonal dimorphism, yet I cannot forbear arranging them, provisionally at least, in reference to our general conceptions of the subject. When, in the year 1875, I first set about investigating the ways of this striking and yet so long neglected phenomenon, I assumed that it was to a certain extent obvious, that this kind of dimorphism was everywhere a direct result of the various direct influences of climate, principally of the temperature, as it effects in regular alternation the spring and the summer brood of manybrooded species. I had also well considered the other possibility, that dimorphism connected with the time of the year might also depend upon the indirect influence of the changing environment, i. e., that it might depend upon the adaptation to the varying environment of the butterfly according to the time of year."

I then said: "It is not inconceivable in itself, that phenomena occur among the Lepidoptera analogous to the winter and summer clothing of Alpine and Arctic mammalia and birds, only with the difference, that the change in coloring does not arise in one and the same generation, but alternately in different ones." But, at that time the fact that the upper side of butterflies, which is usually not adaptive, can be very variable just in summer and spring, sometimes more so than the adaptive under side, appeared to me to contradict this adaptation of seasonal dimorphism. Yet, it was the fact, that the one or the other seasonal form could be produced artificially by the operation of a higher or lower temperature, i. e. the stamp of the winter form might be impressed on the summer brood, and vice versa. I therefore concluded that it was the measure of heat which was acting during the pupal period which directly formed the species in one way or the other; and I felt the more justified in so doing, as the climatic varieties form a parallel to the seasonal forms, and as the former must, without doubt, be referred to the direct influence of climate, especially of temperature.

Thus, for example, Chrysophanus phlaas is seasonably dimorphic in Sardinia and at Naples; the summer form, which develops during the

summer heat, is very dark, almost black, but the spring form corresponds with our German red-golden phlæas.

Although to-day I still look upon this view as correct, and a directly altering effect of temperature as proved, yet I have gradually been convinced, that this is not the sole origin of seasonally dimorphic variabllity, but that there is also adaptive seasonal dimorphism. We must, I believe, distinguish direct and adaptive seasonal dimorphism; and, I see in this distinction an important advance, which, before all, places us in position to explain the results of the various experiments undertaken by myself and others in a much more satisfactory manner.

I have already pronounced this view in a lecture delivered at Oxford in the beginning of 1894, and I have sought to show that adaptive seasonal dimorphism, which I had previously only put forward as possi ble, does actually occur. The example there given for perfect insects was, indeed, only a hypothetical one, viz., the case of Vanessa prorsalevana; but for larvæ, at least, I can select an example from Edward's excellent work on the North American butterflies with tolerable certainty, viz., that of Lycana pseudargiolus, which will be more accurately discussed later on. I did not then know what I learnt shortly afterwards from an interesting little pamphlet of Dr. G. Brandes, that cases of seasonal dimorphism had been known for a long time among tropical butterflies, and that among these, at least, one of the seasonal forms depend upon the assumption of a special protective coloring. Brandes maintains, with justice, that the view hitherto widely held among us is erroneous, according to which seasonal dimorphism was not to be expected in trophical countries, since the alternation of seasons is absent there. Periods of rain and drought, at least for many tropical countries, form such an alternation very sharply. At any rate, Doherty, and, somewhat later, de Nicéville, have pointed out, for Indian butterflies, a series of seasonally dimorphic species, not merely by the observation of the alternation of the two forms in nature, but by rearing the one form from the eggs of the other; thus among Satyridae of the genera Yphthima, Mycalesis, and Melanitis, and for the species of Junonia, it is accepted as proved; and in all these cases the difference between the two forms principally consists in the fact that the one form seems like a dry leaf on the under side, while the other possesses another marking, and at the same time a number of ocelli.

Without engaging in the controversy as to the biological value of these ocelli, I do not for a moment doubt but that the coloring with ocelli is also an adaptive form, possibly protective or intimidating coloring. If one of the two forms had no biological significance, it could

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