:\M Dr. .'t tlu' Ufv. S. GiMliani Bi:ul>--Hiiks on 



jiliort, pioxitnally directeil ridge of the same nature arises 

 from a similar position on the internal border of the lobe. 



Ilal). Bakewell, wiki, in a well-wooded Carboniferous 

 Limestone district, under a stone. 



7'>/pe. Slides 1275 and 127G, tube 1277, Brade-Biiks 

 collection. 



It seems a convenient opportunity to give a diagnostic key 

 to the females of the genus Brachychoiteunia, as follows: — 



1 a. Posterior lobe (of the "cyphopodite ") bmk- 



injr a pair of deHiiite circular thickenings 



of chitin '2. 



16. Posterior lobe funiislied witli a pair of [Hirks. 



detiuite circular thickeninf^s of ciiitin . . B. incliuwpA, Brade- 



2 a. Posterior lobe with a marked median 



elevation 3. 



'2h. Posterior lobe without a marked median 



elevation B. quartum, nobis. 



3</. Posterior lobe witli a small median eleva- 

 tion and well-marked lateral folds of [Brade-lJirks. 

 chitin B. buffnalli, Verlioelf et 



3 b. Posterior lobe with a lar-re and outwardly 



directed median elevation, but lacking [et Brade-Rirks. 



lateral folds of chitin B. bradece, Briilemann 



In the males of the genus it seems probable that develop- 

 ment of the telepodite of the anterior gonopods luns parallel 

 with the development of the posterior lobe of the **cypho- 

 podite'' in the vulva of the female. If that is really so, we 

 should expect that when examples of the male of ^. quartum 

 are found, the telepoditic elements of the anterior gonopoJs 

 \\ ill be similar to those of B. hradeoe and B. hagnalli — perhajjs 

 slightly less complicated; we should not expect the complex 

 condition of the telepoditic horns found in B. inelanops. h\ 

 the species known previously the coxal prolongations of the 

 anterior gonopods have been useful diagnostic features, and 

 by analogy we should expect them to differ in B. quartum 

 from those of the other species and to be siuipler in form than 

 in any of them. Tlius, tiny should most closely resemble 

 the coxal prolongations of B. hagualli'^. Tiie syncoxite of 

 the same gonopods aj)j)ears to be a fairly constant feature, 

 and so it is to be expected that in this character and in the 

 disposition of the pseuduflagella the male of" B. quartum will 

 agree with the other specie-s. 



* The coxal prolongations might, for example, be broader distally and 

 less elevated than in B. bayualli. 



