48 EXPLANATION OF PLATES. 



Plate ii. 



Fig. 1. Athorybia Californica sp. nov., side view, showing 

 a single full grown polypite, tentacles (three are represented), 

 tasters and covering scales. It will be noticed when compared 

 with published figures of other Athorybiae that the float is very 

 prominent and that the mouth opening of the polypite is more 

 trumpet-shaped than is ordinarily the case. This figure was 

 a free-hand drawing made on shipboard. Later a better ex- 

 amination was made on land in which I detected but owe tenta- 

 cle. I am confident that in my first examination three tentacles 

 were seen and so have reproduced my original drawing. 



Fig. 2. A single tentacular knob of the above, showing the 

 peduncle, the involucrum, two terminal and a single median ten- 

 tacles or filaments. The median is inflated into the terminal 

 median vesicle. 



This figure also shows the sacculus. The knob closel}' re- 

 sembles that of other Athorybise and diflTers from that of the 

 young Agalma. A young Agalma of the same age would 

 have those tentacular knobs which I have called "embryonic 

 tentacular knobs" (see figures in Bull. Mus. Comp. ZooL, Vol. 

 viii, No. 9). 



The apical prolongation of the involucrum is a character of 

 the genus Athorybia. This projection is shown on the lower 

 side of the involucrum. 



Fig. 3. View of Velella Meridionalis sp. nov. Seen from 

 above looking down on the float. Compare with the colored 

 figures of Plate i. 



Plate hi. 



Fig. 1. Steenstrupia occidentalis sp. nov. Very much en- 

 larged, showing budding young at the base of the single long 

 tentacle. 



Fig. 2. Young medusa of Syncoryne {Sarsia) occidentalis 

 sp. nov. 



Fig. 3. Adult of the same. Very much enlarged. 



