149 



joint is large, and one of its margins is provided with a row of very short setiform processes. 

 Trunk-legs seem to be altogether wanting. 



THE MALES. They are always distinguished by a very peculiar — though mutually 

 extremely varying — development of the frontal border, the margin of which is in a great 

 measure decorated with numerous fine, or exceedingly small, spiniform processes, which are 

 mostly arranged in a single line. Trunk-legs and caudal stylets either tolerably small, or 

 — frequently — altogether wanting. 



OVISACS. They are middle-sized or pretty small, but exceptionally numerous, for 

 in three of the species occurred about twenty, in a fourth even twenty-eight sacs, which 

 decidedly had been laid by the same female. 



THE LARViE. The front is decorated, either with some good-sized lists, mutually 

 connected on each side, or (mostly) with numerous fine processes, arranged in one or more 

 rows. Each maxillula has four branches. The basal joint of the maxilla? has a double comb 

 of fine, almost cylindrical, apically rounded processes along the margin, against which the 

 second joint is folded (pi. VIII, fig. 3o); the third joint has two or more pointed processes 

 along its inner margin. The second joint of the maxillipeds much shorter than the third. 

 Abdomen of medium length, or (mostly) tolerably long and powerful; first segment good- 

 sized, and the setae proceeding from its posterior angle extending to, or somewhat beyond, 

 the caudal stylets; second segment about as long as or a little longer than the first one 

 and a little more voluminous; third segment very short, and the caudal stylets set off by a 

 distinct articulation. 



1. Conspectus of the Females. 



1. Maxillae well developed 2 



1'. Maxillae quite rudimentary 31. S. mar ■ginata n.sp. 



2. An odd, good-sized, vaulted eminence, provided with a prominent median plate, a little 

 behind and inside the base of the maxillipeds 27. S. decorata n. sp. 



2'. No eminence behind the maxillipeds 3 



3. The head well defined from the trunk, with frontal border and lateral borders well 

 developed. Caudal stylets well developed 28. S. modesta n. sp. 



3'. The head not defined from the trunk, frontal border and lateral borders wanting. No 

 caudal stylets . .- 4 



4. The solid chitine of the genital area surrounds the genital apertures posteriorly and 

 laterally, not anteriorly 29. S.dispar n.sp. 



4'. The solid chitine ot the genital area surrounds the genital apertures on all sides. 



30. S. insignis n.sp. 



2. Conspectus of the Males. 



1. Trunk-legs present 2 



1 '. Trunk-legs (and caudal stylets) wanting altogether 3 



