970 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [44] 



instead of lioiizontal in floating. Its size implies that the animal comes 

 to the surface of the water. At the base of the float, where it narrows 

 into the stem, tliere arises a cluster of undeveloped flask-like bodies, re- 

 sembling" polypites closely crowded together. In this cluster are young 

 polypites (?) of all ages, but none were observed to have tentacles. 

 The polypites are flask-shaped, oblong bodies, the largest bearing (?) 

 two wings or muscular expansions, one on each side (?) characteristic 

 of the genus. In the smaller specimen of Pterophysa, in which the float 

 and axis are present, a little cluster of half-developed polypites below 

 the float is much better preserved than in the larger. In this specimen 

 the axis is very much twisted, and it is impossible to estimate its length 

 with any degree of accuracy, although, judging from the size of the con- 

 tracted stem of Rhizophysa Jiliformis in alchohol in comparison with the 

 same when alive, the axis of Pterophysa must be several feet in length. 

 In the larger specimens of Pterophysa, on the other hand, although the 

 stem is hopelessl.y twisted, many of the polypites are still attached, and 

 several clusters of sexual organs can be seen. It is in this specimen that 

 the characters of the polypite peculiar to the genus are best seen. Many 

 of the polypites, however, are broken from their attachment to the stem, 

 and the arrangement of these bodies on the axis is very diflicult to de- 

 termine. While the stem of Pterophysa becomes tougli and oi)aque in 

 alcohol, the more delicate polypites are more transi)aront, and easily 

 break oft* from their attachments. In the bottle in which the Pterophysa 

 is preserved there are large numbers of these bodies which have fallen 

 from the stem. They {pyt.) invariably have a curved, in profile crescent 

 shape, whether attached to the stem or broken from it. If we exam- 

 ine an individual polypite, we find that the walls on one side are thicker 

 than on the other, and at the same time more muscular, wliilefrom each 

 side* tliere arises (one on each side) a loose uius(\ular flap or wing {pt.) 

 to which is given the name pteron. The distance between the two 

 ptera on the concave side of the ])olypite does not measure more than 

 the third of the whole circumference of the polypite, while the eleva- 

 tion of the ptera above the surface of the polypite, or its width, is less 

 than one-half the distance. The ptera extend from proximal {a) to distal 

 extremity of the polypite, and appear almost wholly made up of strong 

 muscular fibers. The polypites are invariably so coiled that the ptera 

 face the concave surface of the organ from which they arise, or extend 

 in loose folds one on each side of the muscular portion of this structure. 

 The coiled polypites in alcohol have a remote likeness to the larvae of 

 Coleoptera coiled up for defense. They are coiled, both when they are 

 free, or, as often happens, when they tightly embrace the stem, so that 



* The relative position of the wings as compared to the axis could not be observed. 

 The bodies with which I have compared them in B. conifera, according to Studer, are 

 dorsal and ventral. 



