Coxal glands of the Arachnids. 



247 



m 



IV 



Diagram B. 



Comparison between 



the coxal glands of 



the scorpions, pedi- 



palps and spiders. 



1. Scorpions. The 

 saccule {S) surround- 

 ed by the labyrinth 

 coils, which termi- 

 nate in a vesicular 

 dilatation and an 

 outlet on appen- 

 dage V. 



2.Pedipalps.From 

 the saccule the coiled 

 labyrinth tubule ex- 

 tends posteriorly as 

 far as appendage VI, 

 where it turns and 

 runs straight for- 

 wards to the outlet 

 on appendage III. 



3. T h e r a ]) h s i d 

 spiders The two 

 saccules on appen- 

 dages III and V 

 communicate with 

 the coiled labyrinth 

 tubules and through 

 them with the two 

 outlets on III and V. 

 The exact relations 

 of the labyiinth with 

 the saccules and 

 outlets have not 



been determined. 



4. Aran eae verae. 

 Group 2. The Hun- 

 ting Spiders. 



The saccule is exten- 

 sive but tlie tubule 

 leading from it poste- 

 riorly has become 

 straigliteued out and 

 the walls so thinned 

 down that they often CI 



appear fused with 



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

 s-reatly dilated and appears to act only as a vesicle since the lining cells have 

 lost their striation. 



5. Araneae verae. Web Spinners. 



The saccule is well preserved but the labyrinth has become fused with it, 

 with the exception of a short vesicular portion leading to the exit tubule and 

 outlet on appendage III. 



17 



Zool. Jahrb., Supplement XIV. 



IV 



VI 



