24 THE VOYAGE OF H.M.S. CHALLENGER. 



Family Cunanthid^e, Hseckel, 1877. 



Cunanthim:, Hseckel, System der Medusen, 1879, p. 310, taf. xix. figs. 1-3, taf. xx. figs. 1-6. 



Narcomedusse with broad pouch-shaped radial canals or pernemal gastral pouches, which 

 are sometimes simple, sometimes split each into two cascal lobe pouches, but are always 

 connected with the circular canal by double peronial canals, with otoporpse (or clasps of 

 the cordyli) at the basis of the auditory clubs. 



Sub-family, Cunoctonid^:, Hseckel, 1877. 

 Cunanthidse, whose radial pouches bifurcate each into two csecal lobe pouches. 



Cunarcha? Hseckel, 1879. 



Cunanthidse, with four perradial tentacles, inserted in the bifurcation of four perradial 

 gastral pouches, which at the distal part are continued into four lobe pouches. 



The genus Cunarcha is one of the simplest and oldest of all forms of the Narcome- 

 dusse, and is immediately connected with Cunantha, the hypothetic originating genus of 

 this order ; like the latter it has only four tentacles and four alternating collar lobes, 

 but is distinguished from it by the four perradial gastral pouches being continued at 

 the distal end into two csecal lobe pouches ; eight csecal lobe pouches, therefore, lie in 

 pairs between the four tentacles in the periphery of the umbrella collar. This genus 

 forms thereby a very interesting phylogenetic transition between Cunantha and 

 AUgina. By retrograde formation of the otoporpse and the proximal part of the radial 

 pouches it would be transformed into ^Egina. The presence of lobe pouches is common 

 to Cunarcha, and to the genera Cunoctona and Cunissa ; they compose the special 

 sub-family of the Cunoctonidee, whilst the other sub-family of the Cunanthidse, the 

 Cunoctanthidse, have simple radial pouches without lobe pouches (Cunantha, Cunoc- 

 tantha, Cunina), System, p. 314. 



Cunarcha aginoides, Hseckel (PL IX.). 



Cunarcha ceginoides, Hseckel, 1879, System der Medusen, p. 315, No. 329. 



Umbrella cap-shaped, one and a half times as broad as high. Lens of the umbrella 

 biconvex. Umbrella collar with four broad, oval lobes, as long as the radius of the lens. 

 Mouth with long conical oesophagus ; four gastral pouches very broad and short, deeply 



1 Cunarcha. Oldest form of Cunoctonidoo. 



