330 PROCEEDINGS OF THE NATIONAL MUSEUM vol. ii4 



Cambarincola osceola, new species 



Figures 26, 27, 30, 31 



Type specimens. — Holotype and seven paratypes, USNM 29943, 

 from Procambarus paeninsulanus and Cambarus uhleri collected along 

 Dry Creek, 3.1 miles north of Iron City, Seminole County, Georgia, 

 by Horton H. Hobbs and C. W. Hart, September 9, 1955. 



Diagnosis. — A small species of the Vitrea group, very similar to 

 the typical species and possibly a geographic race of it, but differing 

 in the much smaller diameter of the prostate in comparison with that 

 of the spermiducal gland, as well as by differences in the jaw sizes 

 at least in the populations of the two that are geographically most 

 approximate. 



Description. — Essentially similar in body form to C. vitrea, aver- 

 aging perhaps somewhat larger (2.8 mm. in maximum length). Seg- 

 ments slightly more uniform in diameter, although the midbod}^ 

 segments (v-vii) are the largest; caudal sucker generally smaller 

 than the head diameter. 



Head larger than in vitrea, equaling or exceeding diameter of seg- 

 ment I, its length equal to diameter of segment vii. Peristomium 

 distinctly set off and flared, its margin entire except for division into 

 dorsal and ventral halves. 



Jaws larger than in vitrea although of similar form, i.e., aniso- 

 morphic, pentatetradont, the individual teeth well separated and 

 essentially homodont. In lateral aspect the jaws elongate and slender, 

 the lateral cusps elevated and distinct. In specimens from Florida 

 and Georgia, the jaws are subequal in length or the ventral jaw is 

 longer; in more northern material (South Carolina to Vu'ginia) the 

 relationship is reversed with the dorsal jaw distinctly the longest. 



Male reproductive system similar to that of vitrea in most respects, 

 differing chiefly in the lesser diameter of the prostate gland in com- 

 parison with the spermiducal gland : from 50-70 percent the diameter 

 of the latter as against 70-90 percent in vitrea. 



Spermatheca with an elongate, slender, ectal duct which extends 

 into the dorsal half of the coelom and a slightly enlarged ental bulb, 

 the latter generally of greater size than in vitrea. 



Variation. — Most of the observed variation within the limits of 

 this form affect the actual and relative size of the jaws with respect 

 to head length. Similar variation has been remarked in the treat- 

 ment of C. vitrea. 



In the population of southern Georgia and adjacent northwest 

 Florida, the jaws are either of equal median length or the ventral 

 jaw is slightly the longer, and averages from 6-8 percent of the total 

 head length. In the segment of the species which occurs in Virginia 



