4 Carl Bovallius, 



and a part of the pereion into a hyaline bell or globe. The interior of 

 this globe consists of a liquid matter, enclosed in a thin, pellucid mem- 

 brane. As all the specimens I have examined were, since a longer or 

 shorter time, preserved in alcohol, it was impossible to determine if the 

 fluid is specific or the same as the surrounding medium. It was also 

 quite impossible to perceive any connection between this bladder or 

 water-room with the organs of circulation and digestion, or any connection 

 between it and the surrounding medium. How the fluid oi-iginates and 

 is maintained in the bladder, is a riddle, probably not to be solved be- 

 fore fresh specimens of the animal can be examined. 



From the ganglia in the second, third, and fourth pereional seg- 

 ments fine nerves go up to the wall of the bladder, where they spread 

 out in branches. Beneath the bladder, between it and the under-inte- 

 gument of the body, the vegetative organs are placed. 



Uppermost in the second and third segments lies the long narrow 

 heart; the ostia were not very distinct. It sends a strong vessel to 

 the head and another backwards. Close to the under-side of the heart 

 runs the digestive tuhe^ only feebly inflated in the first segment so 

 as to form a stomach. From the pyloric end of the stomach the 

 alimentary canal passes straight to the base of the telson. In the 

 fifth, sixth, and seventh pereional segments, and in all pleonal and ural 

 segments, the canal is fixed by delicate transversal muscles from the 

 sides of the segments. The canal is very wide; the anal orifice, on the 

 under-side of the last ural segment at the base of the telson, is trans- 

 versally ovate, surrounded by muscles. No traces could be detected 

 neither of coeca, nor of liver glands. 



Under the digestive canal lies the chain of nervous ganglia, and on 

 the anterior side of the oesophagus is the uncommonly well developed 

 cephalic ganglion, consisting of a six-lobated, large nervous mass; the 

 two anterior lobes are bent backwards, and attenuated into a stout, semi- 

 circularly bent nerve on each side; these nerves end, a little swollen, 

 in the basal joints of the upper antennœ. From this point the nerve is 

 divided into delicate fibres, passing into a soft glandular substance, which 

 almost fills not only the joints of the peduncle, but also the very long 

 and stout basal joint of the flagellum. This glandular mass is fimbriated 

 corresponding to the serratures at the margins of the joint. Such long 

 fimbriaï run also into the three short terminal joints of the flagellum. 

 From the median lobes of the cephalic ganglion issue the slender nerves 

 for the second pair of antennae. 



