DESCRIPTION OF A LERN^AN CRUSTACEAN (ACHTHERES CAR- 

 PENTERI) OBTAINED BY LIEUT. W. L. CARPENTER, IN 1873, 

 IN COLORADO. 



By A.. S. Packard, Jr., M. D. 



CEUSTACEA. 



AcUJieres Carpenteri, n. sp. (Fig. 1.) — Head about half as long as the 

 body, with very minute conical antennse; the 

 antennal region forming a large rounded lobe. 

 The jaws large, finger-shaped. Anchor, or jaw- 

 feet, large, widely separate; the space between 

 them being narrow-oval, and united by the sucker, 

 which is ot' the general shape of Achtheres. Ab- 

 domen rounded-oval, one-half longer than thick, 

 with indications of three segments; the sutures 

 nearly obsolete, however. Egg-sacs a little 

 longer than the abdomen, regularly cylindrical,., 

 containing from about forty to sixty eggs, the 

 eggs nearly one-half the diameter of the arms of 

 the anchor-feet. Uniformly pale- white. 



Length of body without egg-sacs, 0.15 inch ; 

 with egg-sacs, 0.25 inch. This should perhaps be 

 regarded as the type of a subgenus of Achtheres, 

 which it resembles more nearly than Lernwocera. j^^^^^^^^^ Carpenter! 

 The segments of the abdomen are very faintly ^ 



indicated, and in the form of the head and appendages, and their degree 

 of development, it seems intermediate between Achtheres percarum and 

 Cauloxemis stygius, Cope, from Wyandotte Cave, Indiana. 



Taken from trout, East Elver, August 29 (W. L. Carpenter). 



