NO. 2063. NORTH AMERICAN PARASITIC COPEPODS— WILSON. 615 



the body. Young females and adults, whose ovaries are full of eggs, 

 have a plump trmik, which is not very strongly curved and whose 

 surface is smooth. But adults in which the eggs have been extruded 

 into the egg strings, have a strongly curved body, with deep grooves 

 or wrinkles. Indeed in many of these adults the cephalothorax is 

 folded forward agamst the ventral surface of the trimk, the two 

 almost touching. In these individuals there is a large longitudinal 

 groove on either side of the body above the oviducts, and several 

 transverse grooves, which indicate the body segmentation. The 

 "shoulders" also project strongly in most of the specimens, making 

 a ridge across the back of the neck. The comparative shape of the 

 dorsal surface of the head is shown in figure 48, while the first and 

 second antennae and the first maxillae are also presented for compari- 

 son. The species may be most readily recognized by the compara- 

 tively enormous size of the bulla, by the absence of claws on the 

 maxillipeds, and by the turnmg forward of the egg strings against 

 the walls of the trunk. From Gadd's species extumescens, which it 

 most resembles, it may be told by the greater diameter of the bulla, 

 by the larger size and prominence of the maxillipeds, by the details 

 of the second antennae and first maxillae, and especially by the 

 curvature of the mandibles in extumescens, and the wide gap in their 

 dentition. 



SALMINCOLA BEAN! (Wilson). 

 Plate 32, figs. 52 and 53. 

 Lemaeopoda beani Wilson, 1908, p. 470, pi. 81. 



Host and record of specimens. — Twenty-five females from the gills 

 of the Quinnat salmon, OncorhyncTius tschawytscJiu, McCloud River, 

 California, Cat. No. 29068, U.S.N.M., types of the species. 



Two lots obtained by the United States Bureau of Fisheries at 

 Battle Creek, Colorado, from the same host. Cat. Nos. 38584 and 

 38585, U.S.N.M. 



One lot obtained by Dr. C. H. Gilbert from the rainbow trout, 

 Sdlmo iridens, at Sisson, California, Cat. No. 38605, U.S.N.M. 



Remarlcs. — This species may be distmguished by the comparative 

 length of the second maxillae, by the size and shape of the bulla, 

 and by the distance between the maxillipeds and the other mouth- 

 parts. The contour of the dorsal surface of the head and a side 

 view of the body are here introduced for comparison. 



SALMINCOLA GIBBER (Wilson). 

 Plate 33, figs. 61 and 62, 

 Lernaeopoda gibber Wilson, 1908, p. 469, pi. 80. 



Host ami record of specimens. — Fifty females from the gill arches 

 of the Dolly Varden trout, Salvelinus malma, at Attu, Alaska, June 



