616 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.47. 



9 1906, by the Bureau of Fisheries steamer Albatross; Cat. No. 

 38583, U.S.N.M. 



Remarks. — This species is the most decidedly humpbacked in the 

 genus, and may usually be recognized by this feature. The strong 

 mushroom shape of the bulla and the details of the second antennae 

 are also characteristic. 



SALMINCOLA CARPENTERI (Packard). 

 Plate 33, figs. 54 to 60. 

 Achtheres carpenteri Packard, 1874, p. 612, fig. 1; 1875, p. 587, fig. 237. 



Host and record of specimens. — A number of females with Qgg strings 

 were taken from "trout" in a tributary of the East River, Colorado, 

 by Lieut. W. L. Carpenter, August 29, 1873. Unfortunately none of 

 these original specimens have been preserved. 



Two adult females, one with egg strings, and a young female were 

 taken from a "salmon" 42 inches long at Battle Creek, Colorado, by 

 Dr. Edwin Linton. They have received Cat. No. 43569, U.S.N.M., 

 and will serve as surrogate t}'73es of the species. 



Specific characters of female. — -Cephalothorax about as long as the 

 trunk and turned at right angles to the latter; antennal region 

 separated as a rounded lobe, narrowed basally and widened distally. 

 Trunk a plump ovoid, one-half longer than wide, and so squarely 

 truncated posteriorly that the female without egg strings may be 

 easily balanced in an erect position. On the ventral surface are faint 

 indications of segmentation ; no abdomen, anal laminae, or posterior 

 processes, but a well-defined genital process on the young female, 

 with the remains of spermatophores still clinging to it. In this 

 young female the trunk was slender, cylindrical, well rounded pos- 

 teriorly, and three times as long as wide. First antennae short and 

 unsegmented; second pair biramose, the endopod and exopod about 

 the same length, the former tipped with four minute spines, the latter 

 with two very much stouter conical ones. Mandibles slender and 

 curved, armed with six teeth, the four terminal ones much larger 

 than the two basal ones, and curved. Fii-st maxillae slender, unseg- 

 mented, without a palp, and tipped with a single seta. Second 

 maxillae large and stout and as long as the entire body; buUa of the 

 usual mushroom shape, with a long and slender petiole. 



The second maxillae are much shorter in the young female, and 

 each is enlarged at the tips and joined to the buUa by a distinct 

 petiole. The bases of these arms form a well-defined ridge around 

 the back of the head, even in the young female; maxillipeds with a 

 stout basal joint and a shoit, curved terminal claw. 

 Color (preserved material), a uniform pale white. 

 Total length (wdthout egg strings), 4 mm. Length of trunk, 2 mm. ; 

 of egg strings, 3 mm. Width of trunk, 1.75 mm.; of egg strings, 0.9 

 mm. 



{carpenteri, to Lieut. W. L. Carpenter.) 



