1960] 
Christiansen — Genus Pseudosinella 
2 3 
with scattered setae along the anterior half. Two to three rows of 
setae along the anterior margin of the second thoracic segment. 
Type locality: Tennessee caverns, Tennessee, H. Henrot coll. 
Distribution: major distribution in south-central Kentucky, central 
Tennessee and northeast Alabama ; isolated populations in eastern 
Tennessee and Kentucky. 
Discussion 
This species is the most abundant and most variable troglobite 
form of the genus in North America. No single description can apply 
to all of the available specimens, but the characteristics listed above 
apply to about 6o% of the specimens and with one or another major 
alteration would fit all save about i% of the specimens seen. The 
variation is extensive and can be seen in virtually all characteristics 
so that some specimens resemble P. argentea while others are superfi- 
cially similar to P. gisini) indeed single specimens are often hard to 
place. Analysis of the variable characteristics shows that they are 
definitely geographically determined ; however, since there is no sim- 
ilarity among the distribution of the various characteristics, the sub- 
species concept is clearly not applicable. 
In general there are six characteristics which vary strikingly and 
these and their limits of variation are listed below: 
A) Second thoracic segment, strongly humped to virtually fiat. 
B) Unguis, condition seen in argentea to condition seen in gisini. 
C) Empodial appendage, lanceolate to clearly basally expanded. 
D) Ratio of fourth antennal segment to cephalic diagonal, 3:6- 
5U-5- 
E) Mucro, anteapical tooth middle to near apical tooth. 
F) Eyes, eyeless to two eyes per side. 
G) Pigment, totally white to head and thorax medium blue. 
All in all the majority of the specimens are very similar to the 
form in the description and no one specimen carries very many of the 
variant characteristics. 
Pseudotisinella spinosa Delamare (new combination) 
Figures 59-62 
Troglosinella spinosa Delamare 1949, Notes Biosp’e., 4: 122-4. 
Body elongate with attenuate appendages. Background color dull 
yellowish white with occasional flecks of reddish ( ?) pigment around 
the bases of the antennae. Head elliptical, strikingly longer than 
broad. Antennae with all segments subcylindrical, and fourth seg- 
ment showing signs of ringing and subsegmentation ; apex of antenna 
