REPORT ON THE AMPHIPODA. 1631 



and of the latter "l'abdoruen se compose aussi de sept anneaux." Irhfhyomyzocm 

 squatinx stands under the heading " C. — Abdomen forme de deux articles et termine par 

 deux paires de tiges," and for this the specific description, without any inconsistency, 

 says, " la partie abdominale est relativement extremement courte, puisqu'elle ne se compose 

 que de deux anneaux." But, to compensate for this diminished abdomen, M. Hesse 

 assigns ten segments to the thorax, which would at once remove the species from the 

 Amphipoda and the Edriophthalma altogether. The figure, however, shows plainly that 

 three of these ten thoracic segments belong to the abdomen or pleon. It is a little 

 perplexing that, though fig. 19 gives to this species only two pairs of uropods in accord- 

 ance with the text, fig. 26, on the contrary, depicts three pairs. Ichtlajomyzocus ornatus 

 is placed under the heading "A — Abdomen forme de cinq articles et termine par trois 

 tiges." Fig. 1 represents this species with a very narrow pleon, carrying a pair of 

 uropods at the distal corners of the fifth segment; between these is what looks like a 

 very narrow segment coalesced with the preceding and having the two rami of a uropod 

 attached to its distal end not quite centrally. It is clear that M. Hesse's single specimen 

 was defective. The absence of the telson from this and the preceding species can scarcely 

 be accepted without corroboration. To determine the true position of all these species, 

 further details must be awaited, and their peculiarities seem well worth a careful investigation. 



1874. Dall, W. H. 



On New Parasitic Crustacea, from the N.W. Coast of America. (Published in 

 advance, March 3d, 1874.) Proceedings of the California Academy of Sciences, 

 Volume V. 1873-1874. San Francisco, June, 1875. pp. 254, 255. 



"On examination," Mr. Dall says, "of a small collection of parasites, in the collection of the 

 Academy (presented by Captain C. M. Scammon, and reported to have been procured from 

 a Pacific Right Whale, near the Island of Kadiak, Alaska, in 1873) I find that it contains 

 two species, both apparently undescribed." The first he describes as Cyamus tentator, n. sp., 

 which, he says, " is readily distinguished from C. mysticeti, Dall, by its spiked ' hands ' 

 and knobby branchial segments ; and from C. Scammoni by its straight unequal branchiae, 

 long antennae, knobs, and the shape of the head." The second he describes as Cyamus 

 gracilis, n. sp., and says that " the prominent features of this species are its slender and 

 compact form, short antennae, and weak and inconspicuous posterior limbs." 



Liitken decides that Cyamus gracilis is the same as the species already so named by Roussel de 

 Vauzeme, and Cyamus tentator the same as de Vauzeme's Cyamus ovalis. 



1874. Scammon, Charles M. 



The marine mammals of the North-western Coast of North America, described 

 and illustrated : together with an account of the American Whale-fishery. San 

 Francisco, 1874. 



Of the Californian Gray Whale (Rhachianectes glaueus, Cope), he says, p. 21, " both sexes are 

 infested with parasitical crustaceans (Cyamus Scammoni), and a species of barnacle (Crypto- 

 lepas rhaxhianecti), which are chiefly upon the head and fins." In a footnote Dall's description 

 of " Cyamus Scammoni, n. sp." is quoted from " Proceedings Cal. Acad. Sci., Nov. 9th, 1872." 

 A footnote to the description of the Humpback Whale (Megaptera versahilis, Cope), p. 38, 



