﻿April, 1857.] 



ELLIOTT SOCIETY. 



177 



with the line of the crest being very decided, and considerable. 

 When viewed from below, it reaches quite to that extremity of the 

 bladder which I have called inferior, and stretches backward to 

 within five inches of the opposite extremity, and is slightly less than 

 three inches in length. I have never been able to ascertain with 

 exactitude the number of the main stems which proceed from this 

 as a base. They are short, and disposed in pairs, of which I have 

 counted in one instance twelve, making twenty four in all. One 

 remarkable character observed in eight out of thirteen injured 

 specimens taken at one time, was a peculiar digestive trunk, shorter 

 and comparatively stouter than the other greater trunks situate at 

 the inferior extremity of the bladder, and differentiated from the 

 rest, not only by its form, but in its color, which is that of the 

 reddish blue air-bladder, not the green of the other digestive 

 trunks. In the specimens where this was wanting, since they 

 had all been subjected to injury, I suppose that it had been 

 torn away, before they fell into my hands. This trunk is so pe- 

 culiar in its position as to have the appearance of a small 

 separate compartment of the air-bladder, which appearance was 

 enhanced by my not being able to ascertain positively that it 

 possessed an oral aperture. There were three sizes of digest- 

 ive trunks in addition to the blind sacs in the form of trunks 

 which duatrefages considers hepatic. The largest are those 

 connected with the greater tentaculiform individuals, and are 

 about six or eight, perhaps sometimes more in number accord- 

 ing to the size of the specimen. They have the form of very 

 much elongated flasks, with rounded bottoms and long necks. 

 The general form of the digestive trunks near the inferior ex- 

 tremity of the bladder is like that of those described, with the 

 exception that they are shorter and comparatively a little stouter 

 in appearance and were not connected with greater tentacu- 

 liform individuals as in the case of the great trunks, which 

 moreover are confined to the middle and hinder parts of the elongate 

 area representing the digestive trunk of the basal medusa. In 

 the smallest size of mouth-bearing trunks and in the brown- 

 spotted blind-sacs considered hepatic, I found no distinctive char- 



one of the vertical lines of the disk in the other Siphonophorae, perhaps the two 

 ascending crests of the basal medusa in such genera as Eudoxia and Abyla. On 

 the other hand we must probably refer the expansion of the branching trunk to a 

 horizontal plane. 



