122 AJTKUAL BEPORT. 



minute structure, in the number of joints of the antennse and from Penilia, in 

 having the first joint of the longer ramus shorter than the second. 



The branch which is three-jointed in Sida is not the one which has the short 

 terminal joint. 



Daphnella Winchelli. Herrick. 



This species closely resembles D. Wingii, Baird, but I have no [hesitation in 

 pronouncing it distinct. Length .03 in. Head rather short. Carapace pear- 

 shaped, transparent. Superior antennae short, but appearing on either side the 

 head when the animal is swimming, they appear to have three setse at the 

 extremity. Inferior antennae very long, as long as body. I'he shorter ramus 

 has four setae on the terminal joint and one on the first, while the other ramus 

 carries eight on the terminal joint besides one that is much shorter than the 

 others, and the first joint has four. 



The tail has long diverging stylets, and seems not to have the minute teeth of 

 the D. Wingii. The posterior portion of the front of the shell-margin is ciliated 

 or spined. The back of the head seems to have the same appendage described 

 in Sida. Ova two. This species was found in Minnetonka creek and is named 

 in honor of Prof. Winchell. 



FAMILY POLYPffEMIDiE. 



Genus Polyphemus. MuUer. 



Bibliography ,-^Vo\Y^]i&m\i^, Muller, Cuvier, Latreille, Strous, etc. 



Baird, Brit, Entomost. p. 111. 



Dana, Wilkes' Exp. p. 1266. 



Characters — Body incurved toward the head except the posterior portion of the, 

 abdomen, which projects backward and is very slender, bearing two long spines 

 at the extremity. Head distmct. Rami of posterior antennae three, and four- 

 jointed. 



Polyphemus occldentalis. Herrick. 



Length .25 in. Body excessively incurved, as is the head. Eye large, filling 

 the head. Superior antennae apparently obsolete. Inferior antennae small. 

 Jaws two or three-jointed, three-toothed at the apex. Feet, four pairs, first pair 

 long, apparently four-jointed and three-clawed at the end, basal portion ciliated 

 on the posterior margin. Fourth pair of feet nearly rudimentary. The abdo- 

 men is very long. Found in " Mud Lake," south of Minneapolis. 



Eurycercus lamellatus. Muller? 



Several specimens belonging to Baird 's genus Eurycercus were found, and as 

 far as can be determined they are not specifically distmct from E. lemeUatm, 

 though they are less in size and have a few minor points of difference. 



I append his description, omitting the bibliography : 



"Shell of an ohve color; rather square-shaped, ciliated on anterior margin; 

 ventricose in centre, and arched on posterior edge. Beak rather blunt and short, 

 superior antennae stout, somewhat conical, slightly curved and terminating in 



