186 MESSRS. L. MURBACH AND C. SHEARER ON [JlUie 16, 



The stomach is much distorted with food, but is of the usual 

 quadrangular shape, with oral lobes finely crenulated. The 

 four radial canals pass from the circular tu.be upwards to the 

 gelatinous peduncle, under which they pass downwards to the 

 stomach ; their crossing lies deeper on this account than the point 

 where they enter the stomach (PI. XXI. fig. 3). They are 

 simple. 



The gonads have the frill-like arrangement on the coiu'se of the 

 radial canals, from side to side, similar to their arrangement in 

 other species of this genus, but they are denser and run closer 

 to the circular canal. 



Colour. — This is hard to determine from preserved material, but 

 it is doubtless somewhat similar to the bright colours in other 

 species of this group. 



Habitat. — Unalaska, Aleutian Is., collected by Kincaid. 

 Discussion. — Prof. Kincaid states that this species was collected 

 in a small salt lake in the Aleutian Islands, which was doubtless 

 connected directly with the sea by some underground passage, as 

 its surface rose and fell with the tide. These Meduspe were found 

 clinging to stones by means of their attachment-pads, and when 

 disturbed moved a short distance, then re-attached themselves 

 again. This species probably possesses the sa,me swimming-move- 

 ments so characteristic of the other species of this genus. 



As already stated, the genus Gonionemus was foimded by 

 A. Agassiz for G. vertens, which he procured in the Gulf of Georgia, 

 July 1859. The peculiar angle formed by the tentacles being 

 bent at the adhesive pad oi' sucker was sufiiciently stiiking to 

 suggest the name Gonionemus for the genus. Haeckel (18) 

 subsequently, understanding this name to mean "kneed threads," 

 changed this to Gonynema *, under which name it appears in his 

 ' System der Medusen.' The resemblance of Gonionemus to 

 Melicertum led A. Agassiz to place it with the latter genus in the 

 family Melicertidse, the elder Agassiz (1, p. 348) placing it under 

 the suborder Sertularife. 



Haeckel (18) arranges four of Agassiz's genera among the 

 Trachomedusfe, but placed Gonionemus in the family Caniiotidffi, 

 subfamily Polyorchince, believing, from Agassiz's descilption or 

 drawing, that it possessed lateral diverticula on the radial canals 

 as already mentioned. 



No further notice was taken of this Medusa until one of the 

 present writers, Murbach (32) published a short preliminary 

 report of the occurrence of the genus in the Atlantic at Woods 



* As Agassiz derived the name Gonionemus from yaii'ia and vrijict, Haeckel's 

 assumption that the first part of the name is derived from yovv is wrong, only the 

 last part of his name is right. Yerkes, in a recent paper (Am. Journ. of Phys. vol. vii. 

 p. 181), has changed the name to Gonionema, in this being followed br Perkins 

 (Johns Hopkins Univ. Cir., .June 1902). Since they correctly derive the" first part 

 of the name from ym>ia, why does this become Gonionema and not Gonianewa 

 m the full name ? In preference to further change we have retained the original 

 name. 



