Miscellaneous. 183 
live in general upon animals which inhabit muddy bottoms, such as 
Ophiocoma neglecta, the Linei, and Leptoplana tremellaris. Such 
are Balatro, parasitic on the Limnicolous annelids, and Saccoddella, 
a parasite of Nebalia *. However, the Orthonectida possess neither 
the rotatory apparatus nor the mastax of the Rotifera, nor even the 
bifurcated tail or the pharynx of the Gastrotricha. The most in- 
teresting question to be solved in the history of our parasites is 
whether these animals have remained normally at the planula-stage, 
or have retrograded to this primitive state, just as the Dicyemida 
have returned to the morula-stage, in consequence of parasitism. 
The fact of retrogression does not seem to me to be doubtful in the 
ease of the Dicyemida, which I regard as degraded Turbellaria (the 
Dicyema of the cuttlefish still possesses the bacilli so characteristic 
of the skin of the Planarians). The proofs of the degradation of the 
Orthonectida are far from being so evident; and these animals 
perhaps represent the most interesting step in the complicated 
phylum of the Vermest.—Comptes Rendus, October 29, 1877, 
p. 812. 
A new Species of Chimeera found in American Waters. 
By Treopore Gitt. 
One of the most unexpected discoveries recently made in Ameri- 
can ichthyology is that of a species of the genus Chimera, of which 
a specimen has lately been sent to the Smithsonian Institution. It 
was caught south-east of the La Have bank, in lat. 42° 40’ N., 
long. 63° 23’ W., at a depth of 350 fathoms, with a bait of halibut. 
An attentive comparison of the specimen with individuals of the 
European Chimera monstrosa renders it evident that it does not be- 
long to that species, but is an entirely distinct specific form. It 
may be named Chimera plumbea, and diagnosed as follows :— 
Chimera plumbea. 
A Chimera with the snout acutely produced; the anteorbital 
flexure of the suborbital line extending little above the level of 
the inferior margin of the orbit; the dorsals close together ; the 
dorsal spine with its anterior surface rounded ; the ventrals trian- 
gular and pointed ; the pectorals extending to the outer axil of the 
ventrals; and the colour uniformly plumbeous. 
By these characters the species is readily separable from the 
Chimera monstrosa and other species of the genus.—Bulletin of the 
Philosophical Society of Washington. 
Note on the Habits of Young Limulus. By AtexanperR AGAssiz. 
Mr. C. D. Walcott has called attention to the fact that when col- 
lecting fossils he finds large numbers of Trilobites on their back +; 
* Claus still places Saccobdella among the Hirudinea; and this error 
has unfortunately not been corrected in the French translation of his 
treatise on Zoology. 
+ The preceding investigations were made at the Laboratory at Wime- 
reux, in September and October of the present year (1877). 
} Ann. Lye. Nat. Hist. xi. p. 155, 1875 ; Twenty-eighth Report N.Y. 
State Museum, Dec. 1876. 
