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in the study of the topography of the system and we are left absolutely in the dark as to the presence of ganglia in front of those of the chelicera; a point of no little importance. The eyes receive hardly more satisfactory treatment, owing to the unsatisfactory condition of the specimens. No vitreous body was found in the median eyes while the retinal cells showed no rods, and no grouping of these into a rhabdem was seen. The lateral eyes vary in size, shape, and arrangement and are described in some cases as having fused on either side of the head, although no evidence is presented of such fusion. The pedipalpal organs, reversible sacs on the tips of these appendages are described in detail and are clearly sensory as are the "racquet organs
racquet organs” ou the last pair of thoracic appendages. - The alimentary canal opens by the mouth at the end of the beak, the opening being fringed with a strainer of bristles, while the æsophagus, in front of the resophageal collar, is modified into a “sucking stomach." The midgut is provided with gland, like diverticula and although they are grouped into those of the cephalothorax and abdomen, all clearly belong to one series, but those of the abdomen are remarkable not only from the number but from the fact that they empty into a collecting duct on either side and these ducts, in turn, empty into the intestines near the base of the abdomen. The Malpighian tubules are well developed and are described as emptying into the midgut, and Bernard accepts the views of Loman that these organs in the Arachnids cannot be homologous with the similarly named structures in the Hexapods. The heart has retained 8 pairs of ostia, while there are indications of another segmental chamber in front. From in front an aorta carries the blood forward and “ appears to discharge the blood directly on to the central nervous system. There are no indications of the circumneural vessels like those of the Scorpions and of which Mr. Bernard holds, in some respects, peculiar views.
The respiratory system affords more that is interesting. The observations of previous students that there are three pairs of stigmata (and sometimes a fourth unpaired) is confirmed. Of these the first pair open behind the coxæ of the second pair of legs while the others compare with the anterior pulmonary openings of the Scorpions. Arguing from the conditions of the blood vessels (and more from his preconceptions of the phylogeny of the respiratory organs Bernard concludes that there were originally two other tracheal openings in the thorax. There then follow some interesting but inconclusive remarks upon the primary number of stigmata in different Arachnids. While dealing with these respiratory structures the author deals with the question of the origin of trachea from lung books (p. 375) and accepts the view that the former were the more primitive, the latter secondary, and reinforces it with the remark that this view "arrived at by comparative morphology, has recently been confirmed by embryology. Janorowski has discovered that the tracheal in vaginations of Spiders first from branched, tracheal tubes and that the lung books are a secondary specialization.” And this without the slightest reference to the results of Simmons (since amply confirmed by Purcell and Brauer) which are directly the reverse. It is to be said in passing that the thoracic stigmata of the Solpugidze, like those of the Acarina, are the greatest difficulty presented to those who believe in the Limulus-Arachnid theory, but the author dismisses the results of Wagner in this connection with the remark “that all conclusions based upon transitional phenomena of single specialized types will have ultimately to be tested by a profounder and more extended comparative study of existing forms."
The coxal glands, naturally have much attention. The external opening occurs between legs 3 and 4, the duct is long and convoluted while the gland itself is described as a great mass of tubules. These organs he is still inclined to think the derivatives of setiparous sacs, a view which “has hitherto met with no favor.” Regarding the fact that they may be cælomic in character he merely refers to Lauries observations on the scorpion and says that until this be confirmed the bulk of evidence seems to point to the coxal glands as a blind ending tube. And again (p. 381). “I freely admit that these arguments would have but little weight as against direct embryological evidence, if that evidence were really satisfactory.” Certainly the results of Grobben, Kishenonyi, Lebinsky, Kingsley and especially those of Brauer are confirmative of those of Laurie, all showing the coxal glands are derived from the cælomic wall and are the purest of mesoderm (if there be such a layer) and that their external opening is a subsequent formation, For the opposite view, held by Bernard, there seems not the slightest evidence.
After a few remarks upon the genital organs the author presents an attempt to elucidate the phylogeny of the Arachnida, and it is here that we are most at variance with him. It is impossible to go into his argument in detail. It all rests upon the attempt to derive every existing Arthropod structure from structures already present in the annelid ancestor, setiparous sacs apparently playing the most important point. These coxal glands, trachea, poison glands, stink glands, spinning glands cement glands, maxillary glands, salivary glands, etc., are all referred back to the setiparous gland of the annelid; yes further, the hairy bodies of the Solpugids and Mygalidze are direct inheritances from the annelid setæ. Scorpio is not primitive but rather a specialized form. In some of his statements of fact he also seems to be in error. Thus he says (p. 398) “What actual evidence we have as to the character of the abdominal limbs (in the primitive Arachnid] shows that they were filamentous jointed appendages like those on the cephalothorax.” On the contrary in Scorpions (cf. Brauer, Patten) which, with all deference to Mr. Bernard, we continue to regard the most primitive of existing Arachnids, they appear in the embryo as flat lamellate limbs. Again (same page) he says that the sensory plates on the pectines of the scorpion are on the ventral and not on the posterior face of the limb. On the contrary they are on the posterior side as the figures of both Patten and Brauer show. But what we have most to criticise is the failure to refer to opposing views or corrections of previous statements. Thus he refers to "stigmatic scars" along the whole length of the abdomen of the Pseudoscorpions, scars which bear another interpretation. He speaks of the en tostemite as ectodermal, without stating that a portion of it is mesodermal (Schimkewitsch), while we have referred to other cases above.-J. S. K.
The Bears of North America.'-A new classification of the bears of North America is proposed by Dr. Merriam. This classification is based on the study of more than 200 skulls, including about 35 skulls of the huge bears of the Alaska coast region. The number of full species recognized by Dr. Merriam is ten : 4 of the Black Bear group; 2 of the Grizzly group; 3 of the big brown bears of Alaska, and the Polar bear. Four of these species are new; (1) the gigantic fish-eating bear of Kadiak Island and the Alaskan Peninsula, Ursus middendorfii Merr.; (2) the large brown bear of Yakutat Bay and the coastal slope of the St. Elias Alps, Ursus dallii Merr.; (3) the large brown bear of Sitka and the neighboring islands, Ursus sitkensis Merr.; and (4) the Florida Black bear, Ursus floridanus Merr. The Sonoran Grizzly and the Norton Sound Grizzly are considered as subspecies only. The Alaskan bears fall into 2 distinct groups. (1) U. sitken six and U. dallii, which resemble the Grizzlies in the flatness of their skulls, but are larger and differ from them in color and dentition; and (2) U. middendorffii which differs markedly from all other American types, and closely resembles the Great Brown Bear of Kamschatka. Merriam's synopsis is illustrated by figures of the skulls of the different species.
(Proceeds. Biol. Soc., Washington, April, 1896.)
As an account of the North American bears this paper is far in advance of anything bitherto published.
The difficulty of distinguishing several species of the typical Ursi in North America has not been so much the absence of characters among themselves, as the intermediate position of the old world Ursus arctus with regard to them. Middendorff's studies of this species convinced him that it varied in size 33 per cent. of the largest dimensions, and in other respects, but he could not refer the varieties to more than one species. With these very elaborate studies as a basis, J. A. Allen and A. E. Brown in subsequent years could only see in the North American grizzly and black bears, geographical races. The fault then of Dr. Merriam's paper is, that he has not given any account of the relations of our bears to the intermediate series of the Old World.
Dr. Merriam is a genus fancier, and he bids fair to adopt all of the names of his illustrious predecessor Dr. J. E. Gray of the British Museum. Thus he adopts Gray's name, Thalarctos for the polar bear on characters which do not exist. He dallies with Euarctos for our black bear for equally poor reasons.
We must admit, however, that Dr. Merriam does for the first time give satisfactory characters with which to distinguish this species from the Ursus arctus.
RECENT BOOKS AND PAMPHLETS.
ALLEN, J. A.--Descriptions of New American Mammals. Extr. Bull. Amer. Mus. Nat. Hist., Vol. VII, 1895. From the author.
ANDREWS, C. W.-Note on a specimen of Ceraterpetum galvanii Huxley, from Staffordshire. Extr. Geol. Mag, Dec. iv, Vol. II, 1895. From the author.
Annual Report for 1893 Iowa Geological Survey Vol. III. Des Moines, 1895. From the Survey.
BANGS, 0.-Notes on North American Mammals. Extr. Proceeds. Boston Soc. Nat. Hist., Vol. XXVI, 1895. From the author.
Barret, J. 0.-Forestry in our Schools. Minneapolis, 1895.
BEECHER, C. E.-The Larval Stages of Trilobites. Extr. Amer. Geol., Vol. XVI, 1895. From the author.
BERG, C.-Enumeración sistemática y sinonunica de los Peces de las Costas Argentina y Uruguaya. Buenos Aires, 1895. -Sobre Peces de
dulce nuevos ó poco conocidos de la Republica Argentina. Extrs. Anal. Mus. Nac. Buenos Aires, T. IV, 1895. From the author.
BOULENGER, G. A.-Remarks on some Cranial Characters of the Salmonoids. Extr. Proceeds. Zool. Soc. London, 1895.
-An Account of the Reptiles and Batrachians collected by Dr. A. D. Smith in Western Somali Land and the Galla Country. Extr. I. c., 1895.
-On Fishes from Matto Grosso and Paraguay. Extr. I. c., 1895.
A Synopsis of the Genera and Species of Apodal Batrachians, with Description of a new Genus and species (Bdellophis vittatus). Extr. I. c., 1895.
- Remarks on the Value of certain Cranial Characters employed by Prof. Cope for distinguishiug Lizards from Snakes. Extr. Ann. Mag. Nat. Hist. Lon. don S. 6, Vol. XVI, 1895.
- Description of a new Anolis from Antigua, West Indles. Extr. I. c., Vol. XIV, 1894.
- Description of a new Anolis from Brazil. Extr. I. c., Vol. XV, 1895.
-On some new and little known Reptiles obtained by W. H. Crosse, Esq., on the Niger. Extr. I. c., Vol. XVI, 1895.
- Descriptions of two new Snakes from Usambara, German East Africa. Extr. 1. c., Vol. XVI, 1895.
-Descriptions of four new Batrachians discovered by Mr. Charles Hose in Borneo. Extr. 1. c., Vol. XVI, 1895.
Descriptions of two new Reptiles obtained by Mr. A. S. Meek in the Trobriand Islands, British New Guinea. Extr. I. c., Vol. XVI, 1895.
-On the Reptiles and Batrachians obtained by Mr. E. Lort. Phillips in Somaliland. Extr. I. c., Vol. XVI, 1895,
-On the Variations of the Viper in Denmark. Extr. Zoologist, 1895.
-On a new Typhlops previously confounded with T. unguirostris Peters. Extr. Proceeds. Linn. Soc. N. S. W. S. 2, Vol. IX, 1894. From the author.
Bulletins No. 118, 119, 1895, North Carolina Agricultural Experiment Station.
Bulletin of the U. S. Fish Commission, Vol. XIV, for 1894.
Bultetins No. 24, 25, 1895, Wyoming Experiment Station, University of Wy. oming
CARTER, W. S.-Physiological Action of Kreatin in Normal and Tuberculous Animals. Detroit, 1892. From the author.
CASTILLO, A. DEL Y J. G. AGUILERA.-Fauna Fossil de la Sierra Catorce San Louis Potosi. Bol. de la Com. Geol. de Mexico Num. 1, Mexico, 1895. From the Commission.
Cook, O. F. AND G. N. COLLINS.— The Myriapoda collected by the United States Eclipse Expedition to West Africa in 1889–1890. Extr. Ann. New York Acad. Sci., Vol. VIII. From the author. Cross, W.-Post-Laramie Deposits of Colorado Extr. Am. Journ Sci.,
Vol. XLIV, 1892. From the author.
CROZIER, A. A.-Crimson Clover and Other Topics. Bull. 125, 1895, Michi. gan State Agric. Exper. Station.
Dean, BASHFORD.—The Marine Biological Laboratories of Europe. Biol. Lect. No. 10 delivered at Wood's Holl in 1893.
-Recent Experiments in Sturgeon Hatching on the Delaware. Extr. . Trans. New York Acad. Sci., 1893.
-The Early Development of the Gar-Pike and Sturgeon. Extr. Journ. Morphol., Vol. XI, No. 1, 1895. From the author.