318 bulletin: museum of comparative zoology. 



The characters by which he (1912, p. 14) separates his hrunnea 

 from pileus are that it is more oblong and egg-shaped, by the opaque 

 yellow-brown color of the stomodaeum, and by the presence of termi- 

 nal knobs on the tentacles. But the specimens from near New York 

 and further south were quite as globular in life as any I have collected 

 elsewhere, though now more or less contracted by preservation. The 

 question vs^hether or not the tentacles end in terminal knobs is easily 

 settled in life; and in no case did I see anything which could be 

 interpreted thus. And the tentacles are sufficiently extended in many 

 of the preserved specimens to show that their calibre is uniform to the 

 tip. In many, it is true, these organs are more or less thickened near 

 the end; but this is obviously the result of contraction. Most of 

 the specimens, as might be expected, are so violently contracted that 

 it is impossible to determine anything about the tentacles. As to color, 

 the stomodaeum in many of the southern specimens was of a pale 

 reddish hue in life; but I have also found it so in northern specimens. 

 Furthermore, the proportional lengths of apical canal and stomo- 

 daeum, and the relative level at which the adradial canals join the 

 meridionals in the southern specimens are well within the range of 

 variation of typical P. pileus} In short there is nothing to separate 

 southern from northern specimens except that the former were, as a 

 whole, rather smaller. 



P. hrunyiea may still be worthy of recognition; but it is not con- 

 tained in the Grampus collections, and until specimens agreeing with 

 Mayer's account are reexamined, its status will be dubious. 



Distribution of pelagic coelenterates. 



Pelagic coelenterates fall into two distinct categories according as 

 they are, or are not bound to the coast line by a fixed stage, i. e., 

 they are either neritic or oceanic. And though some genera, for 

 example Niobia, bridge the gap, they are not sufficiently abundant 

 to invalidate the general classification. Among the neritic warm 

 water species are Steenstrupia rubra, Laodicea cruciata, Aequorea groen- 

 landica and the southern form of Cyanea capillata. Probably Caly- 

 copsis typa is also neritic if the term is used in its broad sense, for there 

 is reason to believe that it passes through a hydroid stage on the con- 

 tinental slope (1909b). Omitting it for the moment, however, because 



1 I have been able to compare the collection with a large series from northern waters 



