1902/ 



ANATOMY OF THE PEBIPALPI. 



173 



fore part of the prosoma behind the mouth, have conver^-ed 

 towards one another, so that laterally they embrace the sides of 

 the camarostome or labrum (text-fig. 41, cam.). Dorsally, the 

 proximal portion of the innei- edge on each side forms a hinge- 

 like joint with the adjacent edge of the dorsal wall of the 



Mouth-parts of the Theli/phonidce {Mastigoproctus giganteus). 



A. Timer aspect of the base of the right chela, that of the left side being cut away to 



show the camarostome in place, &c. : ent., median entosclerite rising from 

 the membrane above the liase of the camarostome and affording suijport to 

 the dorsal dilator muscle of the pharynx; cl., pi'oximal plate (clypeus) of 

 camarostome which is articulated to the adjacent area of the coxa of the 

 chela; cam., hairy membranous portion of camarostome {labrum); mS., hairy 

 membranous area of inner surface of the coxa of the chela; m.r.p., maxillary 

 process of the latter ; m., mouth lying beneath the base of the camarostome 

 at the end of the long suboral ti-ough formed by the fusion of the coxse ; 

 p7i., anterior or pharyngeal portion of the stomodfeum or foregut forming, the 

 pre-cerebral sucker of the alimentary canal ; ms., muscular tissue filling the 

 cavity of the coxae of the chelse and of the camarostome ; tr., portion of the 

 trochanter or second segment of the chela; g, groove on the inner (preaxial) 

 side of the coxa formed by an infolding of the chitin. 



B. Dorsal area of the camarostome and of the basal segments of the coxae of the 



.chelae when the anterior end of the carapace and the clielicerae are removed. 



Lettering as in A, with c.r.p., process of coxa which projects into the 

 prosoma and supports the lateral dilator muscle of the pharynx. 



