186 



MR. R, I. POCOCK ON THE 



[June 17, 



carapace. In fi'ont of this channel the two diverticula generally 

 meet and overlap as in some S23iders (e. g. Argyroneta, according 

 to Plateau), but without fusing or communicating. The divei'ticula 

 of the anterior pair, which are so conspicuous in the Thelyphonidfe, 

 remain undeveloped. Those that extend into the coxfe of the 

 3rd, 4th, 5th, and 6th appendages are i-elatively slendei' unbranching 

 tvibes, longei' and moi-e i-egular in shape than those of Thehjphonus. 

 Their relation to the entapophyses of the entosternite difi'ers also 

 from that which obtains in Thelyj^honus and the Spiders, whei'e 

 the five diverticula typically pass with regularity between the 

 four apojjhyses which rise to the sides of the undei- sui face of the 

 carapace (text-fig. 45, 1-4). 



Text-fig. 45. 



oa.m. E. 



Alimentary system of the prosoma of one of the Fhrt/nidce. 



Dorsal view of the alimentary system of the prosoma of a Phrynid {Titauodamon 

 jolmstoni, partially diagrammatic). II-VI. Basal segments of the five pairs 

 of postoral appendages ; cam., camarostome ; ph., pharynx or pre-cerebral 

 sucker of the foregut ; hr., siiboesophageal portion of cential nervous system 

 traversed by the chitiuovis oesophagus which expands into the post-cerebral 

 sucker of the foregut {st) ; 1-4, ca;cal diverticula of the midgut passing 

 between the muscular apophyses of the entosternite, as described in the 

 text ; ao.f., foramen or channel through which the dorsal aorta descends to 

 the ventral region of the body and a pair of muscular apophyses (not shown 

 in fig.) ascend to the middle line of the carapace. 



In the Amblypygi these foui' apophyses are i-epresented by six, 

 the first and second apparently corresponding to the first in 

 Thelyj)lionus and the Spidei'S, the third to the second, the foui-tli 

 and fifth to the third, and the sixth to the fourth. The fourth 

 and last divei'ticulum in Phrynus, corresponding to the fifth and 

 last in Tlielyplionus and the Spiders, passes, as in those groups, 

 behind the last apophysis ; and the first diverticvilum in Phrymis, 

 coi^responding to the second in Thelyphomcs and the Spiders, j)asses 



