252 B- H. BuxTON, 



saccule, there can remain little doubt that it does actually represent 

 the saccule wlien its relations with tlie rest of the g-land are taken 

 iuto consideration. 



At one point in the central lumen of the saccule a funnel like 

 collecting tubule with definite epithelial lining begins and runs as 

 a long narrow duct opening into the labyrinth (photo 35). The 

 labyrinth can be divided into two very distinct parts, the first of 

 which is not a System of coiled tubules, but is more of the nature 

 of a sac with innumerable pouches (photos 37, 37 a). The German 

 Word "Schlauch" would best describe it, but it may be called the 

 "sac of the labyrinth", or "labyrinth sac" {SL) to distinguish it from 

 the true saccule. 



In its simplest form (Paragaleodes), the long narrow multipouched 

 sac runs posteriorly to a little beyond the tracheal Stigmata (TRS) 

 of the thorax which lie in a space between the fourth and flfth 

 appendages (Frontispice and diagram D), where it ends blindly. 

 The walls of the labyrinth sac are lined throughout with tall 

 columnar epithelium without any striation (photos 36, 37 and 45 (SL) 

 show this best); the closely packed nuclei lying at the base of the 

 cells immediately over the limiting membrane of the wall. 



The lumen of the sac is sometimes fiUed with a granulär 

 detritus and wlien this is the case the cells appear worn down and 

 indistinct (photos 37 a, 42a). This part of the labyrinth appears 

 therefore to be a secreting rather than an excreting organ and may 

 be considered as such provisionally. 



The structure and the cells of this part of the coxal gland are 

 something quite different from anything we have hitherto encountered 

 in the labyrinth and for some time I considered it to represent the 

 saccule in a modified form, and took the saccule to be a new 

 structure of the nature of a glomus, but this view proved to be 

 erroneous. 



I find that Beknaed appears to take this mistaken view of the 

 Situation. He observed the two distinct parts of the labyrinth and 

 considers that the proximal part (labyrinth sac, of this article), can 

 be homologized with the proximal or medullary part (Lankestee) 

 of the coxal glands of the scorpions. But he overlooked the true 

 saccule and collecting tubule altogether and thought the outlet was 

 on the third appendage, so that his observations at any rate were 

 incomplete and in some respects actually erroneous. Beenaed also 

 discusses the question whether these proximal parts of the glands 



