Coxal glands of the Araclmids. 257 



graph 44 of a transverse section from Eremohates can be seen on 

 the left of the rostrum at (^0). Just anterior to this point the 

 sheatli closes up again and proceeds to the final outlet {FO in 

 photo 39), a little further forwards. The photograph 44 and dia- 

 gram C show that the side outlet is directed away from the mouth, 

 whereas the final outlet is directed towards it. 



It seems strange that there is no definite vesicle or reservoir 

 near the outlet for storing the products of secretion since these have 

 to travel so far before reaching the exterior, but the exit tubule 

 appears to be distensible. The photograph 38 b shows this condi- 

 tion of distension as observed in a single specimen of SoJpuga, but 

 in all other specimens examined the tubule is narrow and contracted 

 as in photographs (38, 38 a). Perhaps at the moment of death the 

 muscles usually contract and drive out any secretory products which 

 may be present in the exit tubule. 



Phalangitis. 



The Phalangids have not been studied at all closely, but in the 

 few specimens examined, the labyrinth is clearly marked out, and 

 there is an outlet on the fifth appendage. The saccule is small and 

 surrounds the exit tubule, but I have been unable to find the com- 

 munication between it and the labyrinth through the medium of a 

 collecting tubule. These observations simply confirm those of 

 Bruntz. Bruntz also mentions that there is always a large nerve 

 passing through the folds of the saccule. This observation, I can 

 also confirm. 



Summarising the knowledge thus far gained we find that in 

 the coxal glaads of the scorpions, pedipalps and true spiders there 

 is a saccule, a collecting tubule, a labyrinth Avith striated cells, and 

 an outlet either on the third or fifth appendage, while the primitive 

 Theraphosid spiders have two saccules and two outlets; one cor- 

 responding to the third and the other to the fifth appendage. 



In these groups then the coxal glands appear to be quite homo- 

 logous, but the solifugae possess in addition a secreting sac and 

 the outlet is on the second appendage not far from the mouth, so 

 that the gland acts as a salivary as well as an excretory organ 

 and also possibly as a poison gland. 



On examining, without any special object in view, some sec- 



