Charles R. Stockard” _ 515 
and first branchial gills. The complex changes connected with the enor- 
mous growth of this neck tissue, together with the development of the 
large “club muscle,” and the loose connection of the gill lappet tissue 
with the dorsal body musculature are the main causes Spernune to pro- 
duce the translocation of the gills. 
8. From this study of the head organs in embryos of Bdellostoma I 
am led to believe this animal in many respects primitive, while in others 
it is no doubt specialized. There are no reasons for believing it para- 
sitically degenerate. 
Since it is a true jaw bearing vertebrate the term cyclostome should 
no longer refer to it, the less objectional one marsipobranch should be 
used entirely. 
ZOOLOGICAL LABORATORY, COLUMBIA UNIveERSITy, June 4, 1906. 
LITERATURE. 
ALLEN, B. M., o5.—The cye of Bdellostoma stouti. Anatom. Anz., Bd. XXVI, 
pp. 208-211. 
Ayers, H., 93.—Bdellostoma dombeyi Lac. Woods Holl Lectures, pp. 125-161. 
Ayers, H., and Jackson, C. M., oo.—Morphology of the Myxinoidei I. Skele- 
ton and Musculature. Jour. of Morph., Vol. XVII, No. 2, pp. 185-226. 
— oo.—Morphology of the Myxinoidei. Bul. Univ. Cinci., No. 1, Ser. 2, 
Vol. 1, Dec., pp. 5-14. 
Auis, E. P., JR., 03.—On certain features of the cranial anatomy of Bdello- 
stoma dombeyi. Anatom. Anz., Bd. XXIII, pp. 260-281, 322-339. 
ABILDGAARD, P. C., 1792.—Kurze anatomische Beschreibung des Sangers (Myx- 
ine glutinosa). Schrift. d. Berlin. Ges. nat. Fr., Bd. 10, pp. 193-200. 
Btiocu, M. E., 1789.—Naturgeschichte der auslandischen Fische. Th. VII, p. 67. 
12 Thl., Berlin, 1782-95. 
Bonaparte, C. L., 46—Catalogo Metodico dei Pesci Europei. Napoli, p. 9. 
Batrour, F. M., 85.—A Treatise on Comparative Embryology, Vol. II, London. 
BEARD, J., 89.—Morphological Studies. No. 3. The Nature of the Teeth of 
the Marsipobranch Fishes. Zool. Jahrbiichr., Bd. 3, pp. 727-752. 
Buyor, P., gx.—Contribution 4 l’étude de la métamorphose de lV’ Ammocoetes 
branchialis en Petromyzon planeri. Rév. Biolog. du Nord de la 
Brance, is wk 
DEAN, B., 99.—On the Embryology of Bdellostoma Stouti. A General Account 
of Myxinoid Development from the Egg and Segmentation to Hatch- 
ing. Festschr. zum 70 Geburtstage C. von Kupffer, Jena, pp. 221-276. 
Douren, A., 75.—Der Ursprung der Wirbelthiere und das Princip des Func- 
tionswechsels. Leipzig, pp. 1-87. 
83.—Studien zur urgeschichte des Wirbelthierkorpers III. Die Ent- 
stehung und Bedeutung der Hypophysis bei Petromyzon planeri. 
Mitt. Zool. Stat. Neapel., Bd. IV, H. 1, pp. 172-189. 
