io6 



whole length, there is nothing particular to be seen. We therefore do not understand why in 

 the reconstructed figure of Dathyphysa abyssoriiin (PI. Ill, fig. 28) Studer does figure appendages 

 along the upper part, although he seems to think that no nectophores can have been developed 

 as traces of the latter would have been left. 



Finally Studer finds detached "deckstuckartige Gebilde" (PI. Ill, fig. 25) which are 

 siphons, the wing-like excrescences of which have increased in size. We identify these with the 

 younger siphons, whose stalk has probably not yet been developed. And we furthermore suppose 

 that the thread which Studer sketches at the base of these young siphons (PI. Ill, fig. 25) is 

 a young tentacle. We will return to this subject whilst describing Bathyphysa Sibogae nov. spec. 



Of great interest is also Rhizophysa conifera Studer 78 as it is very nearly related to 

 PteropJiysa grandis Fewk. We agree with K. C. Schneider 98 who calls Studer's specimen 

 Pterophysa conifera. Fewkes 84 does not understand how it is possible that by making the 

 transverse section of one of the polypites as is represented on Studer's PI. I, figg. i, 2, or 4 

 he gets a structure such as is shown in PI. II, fig. 18. He forgets however that Studer did not 

 himself make the sketches of the entire specimen (PI. I, figg. i, 2) and that we may expect 

 differences in shape between the younger white coloured siphons and the older, white, yellow 

 and black coloured ones. The transverse section has assuredly not been made through such an 

 older siphon; there is every reason to believe that he used one of the smaller, younger ones. 



We will show how in Pterophysa grandis young siphons have very strongly developed 

 ptera and how these gradually disappear in proportion to the increase in age of the more 

 distally situated ones. 



We will also describe later on how in the very oldest siphon no trace of wings is left 

 and how the siphons then absolutely resemble Studer's figure 4//, Plate I. 



According to Studer (p. 9) the siphons have an exceedingly small stalk by which they 

 are attached to the stem. He speaks of the basal part of the siphon which is somewhat narrow 

 and becomes "stielartig". 



We therefore suppose that there are short-stalked siphons in Rhizophysa conifera^ but 

 of course we cannot say for certain whether this pedicle really continues to grow in older 

 specimens, so as to become as large as those in BatliypJiysa abyssorum. According to this 

 statement, we might suppose that there is some relation between Bathyphysa and Pterophysa. 



Fewkes 84 writes that Studer's Rhizophysa conifera probably belongs to his new genus 

 Pterophysa, on account of the possession of longitudinal bands in the siphons. He describes 

 these bands (ptera) and gives some excellent figures of one of its siphons. In the text we find 

 that tentacles were wholly absent. We were able to examine a very much twisted specimen of 

 Pterophysa which was not the original belonging to the U.S. Fish Commission, but was identified 

 by Fewkes himself and was published in A. Ag.vssiz' "Blake" report. Here we certainly found 

 tentacles, situated at the ba.se of the siphons. The siphons were sessile ; not the smallest 

 indication of a stalk was to be seen. 



Pterophysa grandis is therefore characterized: by the ptera on the lateral sides of the 

 siphons, by the development of long tubular tentacles and by the absence of any stalk at the 

 base of the siphons. 



