44 THE MEDUSAE. 



Neither of these two specimens shows the very long manubrium which 

 Haeckel ('80) believed to be the chief characteristic of this species. So 

 far as the above dimensions are concerned, they fall well within the limits 

 of Vanhoffen's (: 02") more extensive series. The nettle warts are nearly 

 round in the smaller specimen, more oval in the larger, and in both of 

 moderate prominence. The marginal lappets, structures to which the earlier 

 authors attributed considerable systematic value, are about as broad as long, 

 and slightly incised at the margin so as to form two lobes; but the depth 

 of the incision varies even in the different lappets of a single specimen, and 

 therefore cannot be considered of much importance. The bell is less globu- 

 lar than it is usually described for P. cyanella, being considerably flattened at 

 the aboral pole. The gonads in the larger specimens are well developed. 



The ephyrae, taken in Acapulco Harbor, which I refer to this species, 

 closely resemble the ephyra of P. ci/anella (L. Agassiz, '62). 



Color. — In the specimen from Station 4692 the disc was colorless, the 

 gonads, tentacles, subumbrellar surface, and the four perradial ridges of 

 manubrium and mouth arms pink-violet. The specimen from Station 4696 

 was of the same general color but much paler. An excellent colored figure 

 has been given by Brandt ('38). 



Poralia Vanhoffen, 1902. 



This genus was founded by Vanhoffen (: 02", p. 41) for a single fragmen- 

 tary discophore remarkable because of its apparently octoradial type and 

 simple canal system. Unfortunately the entire margin, with all the tentacles 

 and rhopalia, was destroyed, so that he was unable to suggest any systematic 

 relationship for the genus. 



Two specimens in the present collection seem best referred to this genus, 

 although, if this identification be correct, it would seem that the " Valdivia " 

 specimen was immature, and, therefore, that the description of the genus 

 given by Vanhoffen must be modified. Unfortunately none of the three 

 sp(M;imens, so far referable to the genus, has been in good enongli con'lition 

 to ;illow of any satisfactory description, so that it is impossible to tell whether 

 or not the present ones are specifically identical with P. rufescens Van- 

 hoffen, the type of the genus ; but it is best, at least until better material 

 is available, to include them under that name rather than to add a new 

 name on doubtful grounds. 



