312 



PROCEEDINGS OF THE NATIONAL MUSEUM 



Key to Species of the Macrocephala Group 



1. Ejaculatory duct very long, extending from bursa to nearly the middorsal 

 region, spermiducal gland and prostate straight, extending dorsoventrally; 

 head very large, up to a third the total length of the animal (Wyoming and 



Idaho) Cambarincola macrocephala Goodnight 



Ejaculatorj' duvt shorter, extending only halfway up the segment, the spermi- 

 ducal gland and prostate thereby strongly bent, in their ectal third, down- 

 ward to connect with it; head smaller, much less than a third of the total 

 length (Kentucky) Cambarincola holti, new species 



Cambarincola macrocepJiala Goodnight 



Figures 14-17, 19 



Cambarincola macrocephela [sic] Goodnight, 1943, Journ. Parasitology, vol. 48, 



p. 188. 

 Cambarincola macrocephala Holt and Hoffman, 1959, Journ. Tennessee Acad. 



Sci., vol. 34, p. 103. 



Type specimen. — Holotype, USNM 20598, from Pacifastacus g. 

 gambelii collected in Polecat Creek, northern Teton Coimty, Wyoming, 

 by Robert C. Brown, August 16, 1941. This large worm is mounted 

 flattened dorsoventrally, and it is not possible to make out the 

 reproductive systems with assurance. 



Figures 14-18. — External appearance of two species of the Mesochorea section. 14, 

 Cambarincola macrocephala Goodnight, lateral aspect, specimen from Gooding Co., 

 Idaho. 15-17, C. macrocephala, type specimen, Teton Co., Wyoming: 15, Head in 

 dorsal aspect with outline of jaws shown; 16, head in ventral aspect; 17, lateral profile 

 of segments iii-vi. 18, C. holti, lateral aspect, holotype, Pulaski Co., Kentucky. 



