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front pair of legs (P') have grown larger and stand out in front and on each side of the beak (R). The growing embryo again forces off the ariterior end of its deutovum, and the oval end of the egg protrudes through, and is surrounded by another membrane. This is the tritovum. The embryo is now surrounded by the membrane of the tritovum, and also by the deutovular membrane and the original egg-shell, the last two having lost a small portion of the anterior end. During the tritovumstage the fore pair of feet become curved in like claws, and the beak sinks down into the body.
Now the six-footed larva (Fig. 8) breaks through the shell, and closely resembles the adult (Pl. 8, Fig. 9). The first pair of feet modified for grasping the hairs of the field mouse, on which it is a parasite, take the place of the maxillæ, which have been arrested in their development, and the mandibles (pr) assume a style-like form. After one or more moultings of the skin, a fourth pair of feet (p'''') are acquired, and the adult form results, which the author considers as the type of a new family of Acarina. Claparède also suggests the affinity of Myobia to the Tardigrades (Echiniscus and Lydella,) especially from the study of the structure of the style-like mandibles and their supports. We feel convinced, from the study of Claparède's figures and descriptions, that this comparison is very significant, and this has led us to consider the Tardigrades as a family of mites, related to Myobia and Demodex.
The developmental history of Tetranychus is fully given, and he shows that, in regard especially to the mouth-parts, it passes through an Ixodeslike stage, the beak of the young closely resembling that of the tick. Also, in less complete form, that of a species of Tyroglyphus, in which he shows that the genus Hypopus, which strongly resembles Gamasus, is the male state of several species of Tyroglyphus. Such species with Gamasuslike males he states should be separated from the true Tyroglyphi under the name of Hypopus. He also gives the developmental history of Hoplophora. Since many Oribatidæ pass through an Acarus-like stage, he, with Gervais, places them next to the Acaridæ. He likewise describes Myocoptes musculinus (Koch) a form allied to our Dermaleichus pici-pubescentis (see Pl. 6, Figs. 1, 2, 3.). The work is very fully illustrated with ten beautifully drawn folding plates.
The author concludes with a short chapter entitled “ Für Darwin." He considers that many points in the organization of the mites, in relation to their modes of life, confirm the truth of Darwin's theory of the origin of species. He cites the structure of the clasping organs attached to the legs, hy which they are enabled to grasp the hairs of their host, and instances the alternation in form and position of the first pair of legs in Myobia, and their wonderful adaptation for grasping the hairs of the mice on which they live. He also cites the case of a s ecies of Hypopus, in which, as described by Dujardin, there is, on the hinder edge of the abdomen, two scoop-like lips by which they cling to the hairs of their host.
THE GENERATIONS OF WORMS.* -Our readers are already familiar with the strange alternations of generation observed in many of the lower in. testinal worms. Like successions of forms differing remarkably from the parent, probably occur even in the most highly organized annelids. In the present Journal Dr. Malmgren, known by his elaborate works on the Annelids of the Northern and Arctic Seas, cites what he supposes to be another case, referring the species of “Heteronereis” (which had been considered by earlier observers as a good genus, and may be found swimming on the surface of the ocean, as we have observed it on the coast of Labrador), to certain species of the genus Nereis, which live in the mud or swim at the bottom. The actual connection has not been yet traced, but the author is strongly of the opinion that it will be found that the Nereids are the parents of the Heteronereis, and also of the species of Iphinereis, another genus allied to the former.
FLORIDA AND THE SOUTH.|- Travellers and naturalists in Florida will find in this little book a reliable guide to its hunting grounds and sani. tary retreats, by one already well known as a writer on the history of Florida. The traveller should also take with him the articles on the shell-mounds of Florida, by Prof. Wyman, published in our second vol. ume, and those of Mr. Stearns, which are now appearing in the Nat.
ANNALS OF BEE CULTURE.I— We should judge that this annual was a very timely production. The articles, mostly written by the Editor, are such as must interest and instruct bee-keepers, and we gladly hail every publication which has for its aim the improvement of the art and science of bee-keeping. The Editor proposes to issue another annual early in 1870).
NATURAL HISTORY MISCELLANY.
BOTANY. TENDENCY OF FLORAL ORGANS TO EXCHANGE OFFICES. I have before me a curious instance of the tendency which floral organs have to exchange offices. It is a staminate spike of corn well developed, and of normal growth for some five inches from its insertion on the stem, but bearing on its apex a well defined little ear of grain, as regular in structure as those which were born in their accustomed place. I do not know how common this may be, but I never before chanced to see it. — C. J. S.
Siebold and Kolliker's Journal of Scientific Zoology, 1869.
† A Guide-book of Florida and the South, for Tourists, Invallds, and Emigrants; with a map of the St. John River. By D. G. Brenton, M. D. Philadelphia, 1869. 12mo, pp. 136. Penn. Publishing Co. $1.00.
1 Annals of Bee Culture for 1869. By D. L. Adalr, Editor. Louisville, Ky. 8vo, pp. 57.
HERBARIUM OF THE LATE Dr. WALKER-ARNOTT. — The herbarium belonging to the late Dr. Walker-Arnott has, since his death, been acquired by the Glasgow University. Included in this is his magnificent collection of Diatomaceæ, which is contained in three large cabinets, and consists of fully ten thousand specimens, all mounted upon glass slides, ready for examination by means of the microscope. The specimens put up in tubes, from which slides can be prepared, will most likely be acquired by Dr. Eulenstein, the well known German diatomist, who will thus be enabled to push forward, it is to be hoped, the new edition of Pritchard's Infusoria, upon which he has been for some time engaged. The herbarium is a very large one, being contained in twenty cabinets, each of which holds at least four thousand specimens. The botanical library goes with the herbarium, and thus will be stored in a safe resting-place, the results of the labor of fifty years in the life of this eminent botanist. - A. M. EDWARDS.
NEW LOCALITY OF ASPIDIUM ACULEATUM (L.) Sw. This fern, though widely distributed over the globe, is rare in the United States, being confined to a few mountains and high valleys in New England and New York. It has been collected in the White Mountains of New Hampshire, near the summit of Mt. Willoughby, and in the Notch at the north-eastern base of Mt. Mansfield, Vermont-and among the Adirondack mountains, N. Y. To these localities we may now add “Stony Clove," Catskill Mountains, N. Y., — where the writer found it in August of this year, growing abundantly, under conditions very similar to those of Mt. Mans. field Notch. This locality is one hundred and forty miles farther south than any previously known in our country. - John H. REDFIELD, Phila.
A REMARKABLE ECHINODERM. - At the meeting of the Scandinavian Naturalists at Christiania in 1868, Professor Lovén laid before the Zoö. logical section the figures and description of a very remarkable Echinoderm from the Torres Straits (off Cape York), termed Hyponome Sarsi. It forms, in a new and very unexpected manner, a link between the palæozoic and the recent animal life. It is, strange to say, most nearly allied to Cystidea, especially to Agelacrinus, and will, no doubt, when its anatomy shall be known, give us a full clue to the comprehension of this enigmatic zoological type. The animal (which appears not to have lived fastened to the bottom of the sea) resembles a star-fish, with fine short and thick, but dichotomously branching arms; it had no stem. Five ambulacral furrows are present, giving off branches to the branches of the arms, and farther to several small club-like swellings of the skin, covering the superior, or ventral surface; but only these terminal or distal parts of the ambulacral furrows are open; in the rest of their course towards the centre of the disk they are covered up or converted into vaulted galleries, converging towards the central, but exteriorly invisible mouth. This covering up of the ambulacral furrows was effected by means of the limiting plates joining each other altogether from both sides; but that the food is picked up in the open parts and conveyed to the invisible mouth, is demonstrated by the fact that small heaps of small crustacea and other minute animals were found in them. With the exception of a smooth, triangular space on the back, with a group of small pores in the centre (we do not yet know whether these pores are genital ontlets or perhaps play the part of a “madreporite ") the whole dorsal and rentral surface is covered with small irregular calcareous plates; but in one of the interradial areas of the ventral surface arises an anal tube, or “proboscis,” evidently quite analogous to the anal tube of Antedon, Pentacrinus, Rhizocrinus (and all other recent crinoids, with the exception of the little known Holopus) to the “pyramid" of Agelacrinus, Caryocrinus and Cystidea generally, and to the short or long proboscis of most palæ. ozoic Crinoids, with a hard, tessellated cover of the calyx. It has been a great puzzle, that a mouth, separate from the anal “proboscis” could not be detected in most of the palæozoic Crinoids, now we know where to find it. Mr. Billing's discovery of subterminal ambulacral channels, or vaulted galleries, situated quite below the unbroken perisome, and radiating from the arms towards the central part of the disc, shows clearly, when elucidated by the analogy of the half open, half closed ambulacral channels of Hyponome, that the mouth in these old sea lilies was internal, hidden and invisible, and that the “proboscis ” had nothing to do with it, but was simply the excretory part of the digestive system, as pointed out already in 1866 by Dr. Schultze, in his excellent Monograph of the Echinoderms of the Eifel. — Dr. C. F. LÜTKEN, Copenhagen.
THE TENNESSEE WARBLER. — I was much surprised at the statement of Mr. Boardman in the June number of the NATURALIST, that the Tennessee Warbler is a common species in Maine during the spring. In the article to which he refers, I stated that it was rare in New England, rather on the authority of writers on ornithology than as the result of my own observations. Audubon says that the Tennessee Warbler is rare, and that it extends northward only as far as New York. Wilson met with but three specimens. Nuttall makes no mention of it among the birds of New England. Girard never met with it on Long Island; and De Kay says it is rare in the State of New York. I, myself, have never met with more than two specimens.
It is a very curious fact that this bird should be so rare in New York, and yet so abundant in Maine. All the other Warblers that enter New England in the spring pass through New York and New Jersey, where for a few days they are as abundant as they afterwards are in the New Eng. land States. Either the Tennessee Warbler must migrate with extraordinary rapidity, thus escaping detection, or else it must pursue a more westerly route than the other warblers, turning eastward only when it has journeyed a considerable distance north.-T. M TRIPPE, Orange, N. Y.
GOLDEN-WINGED WARBLER. - Dr. Coues in his "List of the Birds of New England” gives this bird as a “very rare summer visitant to the more southern portions. On page 214 of Mr. Samuels' work, I stated that I had found it occurring sparingly in May for several seasons. Since writing what I did I have observed the Golden-winged Warbler more plenty than ever, and as late as the middle of June, and in the same locality early in August with young. I felt, therefore, quite confident that it breeds here. This June (1869) Mr. J. C. Maynard has had the rare good fortune to find a nest and four eggs. Mr. Allen tells me that since publishing his list he has found it at Springfield in summer, and Mr. Jillson, of Hudson, writes me that it breeds in his locality, though I am not aware that he has actually obtained the nest. I wrongly stated in my letter to Mr. Samuels that this species, probably, proceeded North to breed. From my observations and knowledge of the bird at that time, I supposed it did so. Probably this state is about its northern limit on the Atlantic. - H. A. PURDIE, West Newton, Mass., June, 1869.
CORAL SNAKES. - A number of species of very different genera are confounded under this name by the inhabitants of tropical America. Their general appearance is attractive, being banded with red, black, and white. Some of them belonging to the genus Elaps are poisonous, though some of these are very mild and indisposed to bite. Others, belonging to the genera Pliocercus, Erythrolamprus, Ophibolus, Oxyrrhopus, etc., are quite harmless, but can only be distinguished from species of Elaps by a careful examination of the scales and teeth. The mimetic analogy presented by these species with species of Elaps, according to Prof. Cope, is very remarkable.
During a stay of a few days in Greytown, Nicaragua, an alcoholic specimen of a snake, called a “coral” snake and regarded as extremely poisonous, was added to our collection by a resident. Under the direction of Mr. Robert Kennicott, the naturalist in charge of our party, who had devoted several years to the study of reptiles, we examined the snake in question, compared it with other snakes known to be poisonous, and were fully satisfied that it was quite harmless notwithstanding the absurd stories which were related of it. I afterward brought in one of these snakes alive, and after examining the dentition with Mr. Kennicott, and confirming our previous opinion as to its harmlessness, it was preserved in alcohol. Asking Mr. K. what the species was, he answered that it belonged doubtfully in the genus Elaps, as it was a harmless snake, and was perhaps a new species of his own.* Not being a herpetologist, in a recent article in the NATURALIST I adverted to the circumstance, and used Mr. Kennicott's name as he wrote it in my note-book. An esteemed correspondent, in some remarks about the inadvisibility of handling unknown snakes reported to be poisonous, which I thoroughly
* I have since been informed on good authority that the species to which he referred It is confined to Sonora, AMER. NATURALIST, VOL. III.