POLYCH^TA. BENHAM. 185 



He here speaks of a " simple apex." Had he meant to 

 imply that there was a tooth below the apex, he would 

 surely have used the words " apice bidente " as in his diag- 

 nosis of P. {Harmothoe) grisea, on p. 9. 



Grube's account of the elytron in his second memoiri, 

 however, seems certainly to apply to that of the specimen 

 before me, and to those which Willey and Potts describe. 

 He says that they appear, under a feeble magnification 

 (" schwach bewaffnet Augen "), as presenting a network of 

 closely arranged tubercles, which appear rounded, but are 

 in reality polygonal, and each is crossed by a small low 

 "keel" or hght stripe. But are we justified in identifying a 

 worm as L. carinulatus, because it has elytra of apparently 

 the same pattern, when the more important chsetse are so 

 different ? 



I think, therefore, that Willey and Potts had before them 

 specimens of this new species, L. willeyi, and not Grube's 

 species. It is true that Willey describes on the elytra of his 

 worm some large rounded tubercles as " echinulate," but 

 Potts does not find any such marked echinulations, nor are 

 they present in this individual. Probably the short rounded 

 outgrowths above described represent these spines. Potts' 

 account agrees precisely with what I have seen. 



Log. — Off Maria Island, Tasmania, 78 fathoms (with 

 Eunice pycnobranchiata, Physalidonotus rugosus, and Glycera, 

 sp.). 



Genus Physalidonotus, Elders. 



The genus was estabhshed by Ehlers2 for the reception of 

 a worm described in detail by W. M. Thomson^ in 1900 

 under the name of " Lepidonotus giganteus, Kirk," which 

 had been previously named by Quatrefages " Aphrodita 

 squamosa." The leading peculiarity to which the Ehlers' 

 term refers is the possession of branchial " papulae " on the 

 sides of the parapodia, such as occur in the Acoetan 

 genus, Eupolyodontes, and the existence of a definite 

 dorsal channel below the elytra for the passage of the respi- 

 ratory current backwards to its exit between the last pair of 

 elytra ', the mesial portion of the elytra being supported by 

 certain low tubercles or pads of (? muscular) tissue along the 

 back. 



1. Grube- — Annulata Semperiana, 1878, p. 20. 



2. Ehlers— Neuseeland. Annelid., 1904, p. 9. 



3. Thomson— Pruc. Zool. Soc, 1900, p. 974. 



