274 B- H. BuxTON, 



Group 2. 



Plate 22. 



Fig. 25. SeJenops mexicamis (Selenopid). Adult. Sagittal. 250 : 1. 

 Showing the saccule {S) passing into the external tubule 

 (LET) , the walls of which are thinned down , and the cells, 

 flattened so as to resemble those of the saccule. At Ch the 

 lining epithelium of the external tabule changes to that of the 

 internal tubule, the subsequent (internal) course of which is then 

 roughly indicated by the broken lines until it reaches LIT, 

 which then leads to ET, the beginning of the exit tubule. The 

 internal tubule retains some traces of striation, but in most 

 members of this group the striation is entirely lost. 



Fig. 25a. Lijcosa radiaia. Adult. Sagittal. 100:1. 



A view of the coxal gland comparable with that of photo 25. 

 There is an extension of the internal tubule (LIT) over appen- 

 dage III, which ends blindly a little further anteriorly. The 

 Position of the exit tubule and outlet are indicated in brackets. 



Plate 23. 



Fig. 26. Lijcosa radiata (Lycosid). Adult. Sagittal. 40:1. 



The coxal labyrinth (OL) is here converted into a large 

 vesicle. The exit tubule and outlet are clearly shown, but the 

 saccule does not appear in this section. 



(C) Coecum of appendage III. (BIS) Blood sinus. 

 Fig. 27. Tegenaria doniestica (Agelinid). Adult. Sagittal. 100:1. 

 A view comparable to that of 26. 



{CHI) Coecum of appendage III. (NIII) Nerve of appen- 

 dage III. 

 Fig. 28. Zodariid Spider {Si^.?}. Sagittal. 250:1. 



Showing the external tubule {LET) changing to the internal 

 {LIT). In this case the external tubule has become so much 

 fused with the saccule that it is impossible to distinguish between 

 them, except at the point of change. 



Group 3. 



Plate 24. 



Fig. 29, 29a, 29b. Filisiata hibernalis (Filistatid). Adult. Sagittal. 



Three sagittal sections of the coxal gland, from the same 

 specimen, taken at different points. 



The thin walled external and internal tubules of the labyrinth 

 have become so fused with the saccule that it is impossible to 

 distinguish between them. In these sections the glomeruli are 



I 



