1902. 



ANATOMY OP THE PEDIPALPI. 



183 



to their points of attachment to the middle line of the posterior 

 half of the inner surface of the carapace (text-fig. 44, sa"). 



In front of this space ai'ises a median unpaired diverticulum 

 which extends forwards between the diverticula of the anterior 

 pail- ; and protruding on each side of it may be seen a second pair 

 of mviscles which run to the carapace from the branch of the 

 entosternal apophysis just mentioned (text-fig. 44, on., sa'). 



Text-fig. 44. 



VT.X f>. 



Alimentary system of the prosoma of the Tlielyplwnidw. 



Prosoma of one of the Tlielt/phonidce {Hypoctontis formost(s), with carapace, 

 camavostome, and chelicera; removed. II-VI. Basal segments of the five pairs 

 of postoral appendages ; mx.p., maxillary process of coxa of chela ; lam., 

 spoon-shaped plate which underlies the camarostome; 1-5, lateral caecal 

 diverticula of midgut ; m., anterior median diverticulum of midgut ; t'-t"'\ 

 the four lateral apophyses of the entosternite representing the tergo-sternal 

 muscles ; sa', anterior branch and sa", posterior branch of the supernumerary 

 apophysis : ao.f., foramen through which the aorta descends to the ventral 

 region of the body and the muscular apophyses (sa") ascend to the median 

 line of the cara^iace. 



The ariungement of the remaining diverticula with regard to 

 the four pairs of lateral tendinous processes of the entosternite is 

 typically as follows : — The fifth or last pair passes behind the 

 fourth or last process, the fourth, third, and second respectively 

 between the fourth and third, third and second, second and first 

 apophyses of this plate ; the first, as ah-eady described, running 

 straight forwards on the inner or admedian side of the first 



