Coxal glands of the Arachnids. 



247 



Diagram B. 



Comparison between 



the coxal glands of 



the scorpions, pedi- 



palps and spiders. 



1. Scorpions. The 

 saccule (iS) surronnd- 

 ed by the labj'rinth 

 coils , which termi- 

 nate in a vesicular 

 dilatation and au 

 outlet on appen- 

 dage V. 



2.Pedipalps.From 

 the saccule the coiled 

 labyrluth tubule ex- 

 tends posteriorly as 

 far as appendage VI, 

 where it tiirns and 

 runs straight for- 

 wards to the outlet 

 on appendage III. 



3. Theraphosid 

 spiders. The tvvo 

 saccules on appen- 

 dages III and V 

 communicate with 

 the coiled labyrinth 

 tubules and through 

 them with the two 

 outlet s on III and V. 

 The exact relations 

 of the labyrinth with 

 the saccules and 

 outlets have not 



been determined. 



4. Araneae verae. 

 Group 2. The Hun- 



ting Spiders. 



The saccule is exten- 

 sive but the tubule 

 leading f rom it poste- 

 riorly has beconie 

 straiglitened out and 

 the walls so thiuned 

 down that they often 

 appear fused with 



tbe saccule. The tubule leading anteriorly to the outlet on appendage III is 

 ffreatly dilated and appears to act only as a vesicle since the liniug cells have 

 lost their striation. 



5. Araneae verae. 



The saccule is well 

 with the exception of a short vesicnla 

 •outlet on appendage III. 



Zool. Jahrb., Supplement XIV 



Web Spinners, 

 preserved but the labyrinth has become fused with it, 

 portion leading to the exit tubule and 



17 



