EUPAGURUS. 525 



and dissected. The antennary gland will not take the 

 coloration, but the rest of the system will be distinctly 

 outlined. It will be found that the colour has also 

 appeared in the excretory cells of the gill axis. 



In an injected specimen it will be found that there 

 is an antennary gland situated in the front of the 

 cephalon behind the second antenna, which communi- 

 cates with a diffuse and complex spongy mass in the 

 thorax leading to a thin-walled bladder, the nephrosac, 

 in the abdomen, all of which represents the "bladder" 

 of other Decapod Crustacea (fig. 29). 



Except for the abdominal nephrosac and the median 

 ventral thoracic mass, the system is paired. 



1. The Antennary Gland (g.g.) consists of two parts, 

 which communicate with each other, an inner— the end 

 sac (" saccule ") which is surrounded by an outer — the 

 labyrinth. The whole is somewhat kidney-shaped and 

 has a lobulated appearance. The connection with the 

 bladder arises from the upper side, above the notch, and 

 the artery supplying the gland passes in a little lower. 



The end sac is slightly exposed on the dorsal surface 

 of the antennary gland. Its cavity is broken by blood 

 lacunae and by the extensive ramifications of its walls. 

 Sections show that few prolongations arise from its 

 dorsal side. The walls are irregular, and are often more 

 than one cell thick. The cells are large and squamous, 

 the nucleus is spherical and at the base of the cells, and 

 the protoplasmic contents are light staining and finely 

 granular. The borders of these cells are irregular and 

 protuberant, and oil globules are often present (fig. 32). 



The labyrinth is an intermediate duct between the 

 bladder and the end sac, whose cavity has become 

 excessively convoluted by ingrowths from its walls. The 

 epithelium lining this portion is very distinct from that 



