388 bulletin: museum of comparative zoology. 



These few specimens add nothing to previous accounts. The most 

 interesting fact is that this species, found in such abundance by most 

 expeditions to warm seas, should have been so rare in the region 

 traversed by the Bache. 



Aglantha Haeckel, 1879. 



Vanhoffen (1913) has recently united this genus with Aglaura: but 

 though the two are close allies, and each contains at most but one or 

 two species, the difference in the location of the gonads (at the ex- 

 tremity of the peduncle in Aglaura, on the subumbrella near the base 

 of the peduncle in Aglantha), seems sufficiently important to warrant 

 the retention of Aglantha. The impossibility of distinguishing two 

 species in this genus, based on the number of otocysts, has now been 

 fully demonstrated by Vanhoffen (1912a), by Mayer (1910), and by 

 my own studies on a large series of specimens of all sizes from northern 

 waters, both Atlantic and Pacific (1909c; 1913). All belong to A. 

 digitale. 



Aglantha digitale (Fabricius). 



Medv^a digitale Fabricius, 1780, p. 366. 



(For S3monymy, see Mayer, 1910, p. 402). 



Station 



10.157 18-0 meters, 5 fragmentary specimens all about 10 mm. high. 



10.158 600-0 meters, 1 fragmentary specimen, 10 mm. high. 



None of the specimens are in good enough condition to show the 

 otocysts, but all have gonads, in spite of their small size. They are 

 interesting chiefly for the record of occurrence. 



Rhopalonema velatum Gegenbaur. 



Rhopalonema velatum Gegenbaur, 1856, p. 251, pi. 9, p. 1-5. 

 (For synonymy, see Bigelow, 1909a, p. 129). 



This species was taken at Stations 10,161, 10,162, 10,166, 10,169, 

 10,171, 10,173, 10,176, 10,178, 10,180, 10,182, 10,188, 10,192, 10,195, 

 10,196, 10,200, 10,202, 10,203, 10,206, 10,208, 10,209, 10,211, 10,212, 

 in hauls varying from the surface to 1,000-0 meters. 



Most of the specimens are fragmentary, having lost tentacles and 

 otocysts. But the length, at least, of the gonads can usually be traced, 

 even when the organs themselves are destroyed. And this, together 

 with the number (8) of canals, the characteristic outline and especially 



