624 PROCEEDINGS OF THE NATIONAL MUSEUM. 



Island in Lake Superior. Fortunately some of these specimens have 

 been preserved and are now in the Museum collection. They are 

 labeled by Smith himself as "Cotypes" and are numbered 39575, 

 U.S.N.M. There is also a single specimen, a female without egg 

 strings, taken from Coregonus clupeiformis at Sand Island, Lake 

 Superior, b}^ Milner at the same time as Smith's original types. 



This may, therefore, be fairly regarded as another paratype of the 

 species. It is numbered 38563, U.S.N.M. Kellicott reported the 

 species as "found during the greater part of the year on the lake 

 herring, Argyrosomus aHedi, taken by fishermen along the Niagara 

 River. It prefers the fins, though taken from various parts of the 

 body." Two specimens were also taken from the kieye or chub of 

 Lake Michigan, Argyrosomus hoyi, off Kenosha, Wisconsin, Novem- 

 ber 6, 1894, by C. H. Stevenson. They were identified by Gurley 

 and are reported in his manuscript. 



Specific characters of female. — The largest species of the genus with 

 a total length, including arms and egg strings, of 17 mm. Cephalo- 

 thorax in line with the trunk, broadly rounded posteriorly, strongly 

 narrowed and elongate anteriorly, the lateral margins straight or 

 even slightly concave. Trunk pear-shaped, narrowed to a neck 

 where it joins the cephalothorax, obliquely truncated posteriorly, 

 leaving a small conical projection at the center, which represents the 

 abdomen. Trunk indistinctl}^ segmented, showing transvei-se grooves 

 and lateral indentations. Egg strings cylindrical, relatively long 

 and narrow, straight or slightly curved toward each other at the 

 center. Kellicott says, "In some cases I have found them to termi- 

 nate in an apparent straight, sharp spine, a fifth or more as long as 

 they." Eggs small, arranged in 4 or 5 longitudinal rows, from 100 

 to 125 eggs in each sack. First antennae stout, three-jointed, 

 reaching well beyond the tip of the mouth tube, and terminated by 

 three small setae. Second antennae with a stout basal portion and 

 a small endopod (dorsal), which is swollen and armed with stout 

 spines and short bristly hairs. The exopod (ventral) is indistinctly 

 segmented and terminated by three larger curved spines, turned out- 

 ward, and many smaller ones between them. Mandibles with four 

 stout distal teeth, a smaller terminal one, and two or three small 

 proximal ones; first maxillae small and two pointed; second maxillae 

 long and slender, tapering regularlv from the base to the tip; bulla 

 ovoid and supported on so short a pedicel as to appear sessile; max- 

 illipeds stout, reaching nearly to the tip of the mouth tube, terminal 

 joint cylindrical and fleshy, the same diameter throughout and ter- 

 minated by a tiny spine, the other two joints moderately swollen. 



Total length (excluding egg strings), 8 mm. Length of cephalo- 

 thorax, 2.5 mm.; of trunk, 5.5 mm.: of egg strings, 6 mm. Greatest 

 width of trunk, 2.5 mm. 



