OF CARBONIFEROUS MYRIAPODS. 291 



investigations particularly of those articulates of the older rocks whose affinites have not 

 been satisfactorily settled. 



It only remains to give descriptions and refer to illustrations of the species of the two 

 groups whose general affinities have been discussed. 



Suborder ARCHIPOLYPODA. 

 Family Euphoberidae. 



Trichiulus nov. gen. (e p i|, t«\o S .) 



Segments from three to four or five times broader than long, covered closely with toler- 

 ably large papillae, which are arranged in definite series both longitudinally and trans- 

 versely, and support long flexible hairs, which together form a sweeping mass covering the 

 whole body. 



These points will serve abundantly to distinguish this genus from the other Archypoly- 

 poda described in my previous paper on the subject. They are derived from the study of all 

 the species described below, no one of which, however, presents them all ; only one of them 

 shows the sweeping mane of hair enveloping the whole creature ; the others either have 

 no hair preserved at all, or at most vague appearances of a mat of hair next the integument ; 

 on the other hand die specimen showing the hair so well shows nothing of the papillae 

 which (doubtless) bear them, and which show to perfection in most of the other specimens. 



The number of segments appears to vary considerably, from about 20 or more in one 

 species to 35 or more in another ; the form appears to be nearly the same in all, the body 

 being much larger at the front than at the hinder extremity, and tapering pretty steaddy 

 toward the tail ; in one, however, which is fragmentary, no sign of this change is shown. 

 The head end also tapers, but only just next the head itself so far as known, in this respect 

 differing from other Archipolypoda. The head itself, too, joins in this rapid diminution 

 entirely, instead, as in most other Archipolypoda, of being considerably larger than the 

 segments just behind it; its outline, however, is perfectly preserved in only a single speci- 

 men, so that this statement should not be taken as absolute. The various species differ 

 from each other in the form in which the body varies in proportion, in the number and 

 relative proportions of the segments and in the frequency and arrangement of the papillae 

 or tubercles from which the hairs originate. 



Trichiulus villosus nov. sp. 

 PI. il. fig. -L 



Body composed of more than thirty segments which vary from two to three times as 

 broad as long, being broadest in the stoutest part of the body; it is broadest from the 

 third to about the tenth segment and then tapers very regularly to less than half the 

 diameter at the hinder extremity ; the anterior extremity of the body in front of the third 

 segment tapers very rapidly and considerably, the head being only a little larger than the 

 tail — a point seen best in the reverse of the specimen drawn and not appearing on the 



MKHOIBS BOST. SOC. NAT. HIST. AOL. Ill 38 



