948 



REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



[22] 



ances corresponding to the sausage-like bodies of the exumbrella. From 

 the base of attachment of each tentacle to the abaxial end of the radial 

 prominences there extends a short conical spur or rib which recalls 

 similar structures in certain Narcomeduspe. 



The lower floor of the umbrella (subumbrella) is made up of a power- 

 ful zone, formed by a sheet of muscular fibers scantily developed near 

 the abaxial periphery, but larger and more pronounced near the axial 

 border. The ovaries, stomach, and all those organs which occupy the 

 central portion of the subumbrella are wanting in the specimen before 

 me. They probably closely resemble the same structures in the genus 

 Nauplianta. 



Family EPHYRID^, Haeckel, 1877. 



Bphyroides, gen. no v. 



(Plate VII.) 



There are several small medusae, members of the family of EphyridsB, 

 which cannot be identified as belonging to any described genus. In 

 these medusa3 it was very difticult to investigate the structure of the 

 subumbrella, although in two specimens at least the umbrella on the 

 exumbral side could be easily studied. One specimen in particular (Sta- 

 tion 204:li) shows such a characteristic exumbral surface of the disk that 

 there was no hesitation in referring it to an unknown and undescribed 

 geiuis. The distinguishing character of Ephyroides is the presence of 

 from sixteen to thirty-two, or more, rounded, radial ribs on the peripheral 

 zone of the exumbral surface of the disk, alternating with the same 

 nunjber of prominent marginal lappets. These elevations recall similar 

 structures in the Periphyllidse and Collaspidse, but while in these fami- 

 lies we have the elevations very broad and the radial depressions ap- 

 l)earing as narrow trenches separating the elevations, here the elevations 

 are narrow, forming slight ridges, while the spaces between them are 

 broad, flat, equal to the width of the marginal lappets of the umbrella. 

 The radial elevations on the exumbral surface of the bell recall the 

 coronal sculpturing of the Collaspida^ and Periphyllidaj, and it may be 

 supposed that Ephyroides is an ancestral genus connecting the genus 

 Ephyra with such genera as Ifaiiphaiita, Atolla, and Periphylla. 



Specimens of Ephyroides were collected by the Albatross at the fol- 

 lowing localities : 



