1884. ] Zoölogy. QI 
considers this small group of Hydrozoa, which is found wher- 
ever the influence of the Gulf Stream extends, to have greater 
affinity to the Tubularians than to the Siphonophoræ proper. 
Velella mutica is extremely abundant in the Straits of Florida, 
and sometimes finds its way north to Newport and Nantucket. 
It is larger than the Mediterranean species. The young differs 
greatly in appearance from the adult. The Florida Porpita, P, 
linneana, is also much larger than the Mediterranean species. 
In nearly all the Tubularians the base of the cœnosarc extends 
either as filaments or rootlets over a considerable space; these 
filaments are tubular, and, in Hydractinia especially, the base of 
the ccenosarc resembles in structure the float of Porpita., The 
great difference is that in the Porpitide and Velellide the ex- 
tension of the ccenosarc is consolidated into a float from which 
the polyps depend. 
Worms.—M. Megnin has contributed to the Bull, de la Soc. 
Zodlogique a study of the organization and development of Ech- 
inorhynchus, the most important result of which study is the 
proof of the existence in the larve of a well-developed digestive 
apparatus which atrophies without completely disappearing in the 
adult. In the latter the great development of the reproductive ap- 
paratus and the pronounced activity of the generative functions 
overshadow all other functions. The presence of a bifurcated 
intestine brings Echinorhynchus nearer the Trematodes and re- 
moves them from the Nematodes near which there was a ten- 
dency to place them. 
Tuntcates —W. K. Brooks (Zool. Anzeiger, May, 1882) claims 
that the solitary Salpa is a true female, which produces a chain of 
_ males by budding and discharges an egg into each of them before 
birth. These eggs are impregnated while the zooids of the chain ` 
are very small and sexually immature, and they develop into 
females which give rise to other males by budding. Thus there 
iS a remarkable difference in the mode of origin of the two sexes, 
but since both are the offspring of the solitary Salpa, one by bud- 
ding and the other by sexual reproduction, it is not a case of 
alternation of generations. This view, first put forth in the Bull. 
us. Comp. Zodl., No. 14, is again asserted in answer to Salen- 
sky, who claims that what Professor Brooks styled an ovary is 
but a mass of undifferentiated embryonic cells which gives rise 
both to the ovaries and to the digestive organs of the chain salpe. 
Examination with a high power proves, however, that the organ 
_ 48a true ovary containing eggs, while the digestive organs of the 
chain salpz are not formed from it. 
Crustacea.—In the Proc. U. S. Nat. Museum Professor S. La 
Smith gives a list of the Crustacea dredged upon the coast of 
Labrador by the expedition under the direction of W. A. Stearns, 
and also gives a review of the marine Crustacea of that region, 
