164 EXPEDITION TO POINT BAKROW, ALASKA. 



TRACIIYMEDUSA. 



citrai Ksch. 

 Aylanthit Camtisditttii-o llacek. (sp. A. Ag.). 



HYDROIUA (GONOP11OKE3). 



Oemmai'iit ? 

 Mcliccrtuin sp. .' 

 Nn>:ii(t rontirin Ilaoi-k. 

 Stttia-ophoru Mcftfiinii f Br. 

 Medusa resembling Turris. 



Chrysaora melaiiaster BP.ANPI 



1'mbrella flat, disk-shaped; radius, a little more than height; diameter, 1 foot. Aboral sur- 

 face marked with K! radial stripes of brownish color; 32 marginal lobes, each rounded and 

 destitute of marginal teeth. Sense lappets slightly broader than the tentacular. Oral arms 4 in 

 number: length, 3; stout at common origin, tapering to pointed extremity, and abundantly 

 fringed with folds on inner margin. Sense bodies, 8. Tentacles, 2-1; length, 3'. There are 3 ten- 

 tacles lictween each pair of sense bodies. Color, bell, mouth arms, light brown; radial stripes of 

 the umbrella darker; tentacles, dark brown; frills on the oral arms, reddish. Locality, Point 

 Barrow. Taken in August, 1883. 



From the colored sketches it is not difficult to distinguish this species as ('. mdaiiustcr. Of 

 other species which the drawings resemble might be mentioned the closely-allied C'. hcleola Brandt. 

 They differ from the latter in not having teethed marginal lappets, in the tentacles being shorter 

 (in helvohi they are as long 'as the. mouth-anus), and in the colors. The colors agree more closely 

 with those of ('. m<-l<tn(tnter than of helrolu. There are, however, several differences. The varieties 

 of color in C. mediterranea from different localities have been described by Ilaeckel, and, consider- 

 ing the great variation which lie has shown to exist in the same species, we must not lay any great 

 stress on differences of color as a distinguishing feature of different species of Chrysaora. 



The species (C. melaiiaatcr), according to Brandt, is never "less than a foot in diameter" 

 (meaning, of course, the adult). Mr. Murdoch's drawings, therefore, represent small, perhaps 

 young, specimens. The sixteen accessory, small, marginal lappets, which in older forms differen- 

 tiate themselves from the sixteen ocular lappets, are not represented in the drawings. \Ve may 

 account for their absence from the youth of the specimens drawn. 



-Sigma citrea E.srir. 



Since the original description of this species by Esehscholt/ in 1829 it has never been reob- 

 served. The locality from which the specimen which he described was taken is 34 N. Int., 201 W. 

 long., North Pacific. 



Ksdischoltz described two species of ^Eyinit, A. ronea and A. cifrca. The sEginu, collected by 

 Mr. Murdoch resembles more closely the descriptions of the latter. 



Alexander Agassi/,, in "North American Acalepliie," described from Nahant, Mass., a new 

 genus of hydroid jelly-fishes, which he called ('amixtnellu (sp. pachyderma) ; this genus is referred by 

 1 laeckel to .Kylnn, under the name of A. iiachydenna. The anatomy of ^umpnncUa is very different 

 from that of .-Eyina, and unless, with Ilaeekel. we regard Iliese differences, following Alexander 

 Agassi/.'s descriptions, as "BeobachtungS fehlern," we can hardly look upon the two as belonging 

 to the same genus. If Camptuulla is generically different from .-Eyin, it is necessary to substitute 

 the, name .-Eyinnrld Ilaeckel for it, since, as Ilacckcl has well observed. CumpanclUt was applied in 

 l.SL'f) to an Infusorian. A new description is necessary before we can certainly know that ^-Eginaria 

 is generically different from ^Kgiim. 



Of other species of .Eyina, A. rhotUna Flaeck. and A. ('<nnn'ici:iit Haeck. were found in the 

 ('. tileries. and .1. /,' .:, -It*, /ntlt^li Ilaeek. in the A /.ores. The six known species, according to Haeckel, 

 "geho'ren siimmtlich der \viirmeicn /one dcr uordlichen Krdhiilfte." Mr. Murdoch's observation 

 of .-I. i- it rat in the Arctic- Ocean shows, however, that the genus has a wider distribution as far as 



