Mr. J. Lubbock on tivo new species o/Calanidae. 115 



XIII. — On two new species of Calanidae, with Observations on 

 the Spermatic Tubes of Pontella, Diaptomus, ^r. By John 

 Lubbock, Esq., F.Z.S. 



[With a Plate.] 



Whex, in last Marcli, I described the new species of Labidocera, 

 which I proposed to call L. magna, I was only acquainted with 

 the male, and was therefore anxious to find a female in order to 

 complete the description of the species. This is the more neces- 

 sary in the present genus, because the best specific characters 

 are taken from the right anterior antenna of the male and the 

 fifth pair of legs, organs which are dissimilar in the two sexes, 

 and it is thei'cfore evident that unless they are known in both, 

 it would be ver}' difficult to refer females to their respective 

 males. Prof. Owen and Prof. Quekett, with their usual kind- 

 ness, afforded me every facihty, but I was unsuccessful in my 

 search, and have never met with, a second specimen. Dr. 

 M'Donald, however, of H.M. steam-vessel Torch, has recently 

 met with it in great numbers in the voyage from St. Vincent to 

 Rio Janeiro, and a short description of it will be found in the 

 Proceedings of the Royal Society for April 7, 1853. His paper 

 is accompanied by drawings, to the beauty and general accm-acy 

 of which I can bear witness, from which it appears that the 

 colour, as in L. Darwinii, is blue. Anomalocera Patersonii, 

 which is the representative species in the North Atlantic, and 

 appears fo form the connecting link between Labidocera and 

 Pontella, is also greenish blue. I think it likely that the other 

 species are also bluish. Dr. iPDouald says, that when they 

 were " placed in a vessel of sea-water, they rested on their an- 

 tennae on reaching the bottom, and paddled themselves about by 

 their fore-limbs and tail." He has also an interesting observa- 

 tion on the superior development of the right side of the body ; 

 he " remarks that in all their movements the males exhibit a 

 tendency to turn towards the left side, and concludes the ratio- 

 nale of this fact to be, that the brain on the right side being 

 more developed at the part from which the right antenna derives 

 its nerves, a coiresponding preponderance is given to the power 

 of the locomotive organs on that side.'^ 



Although however disappointed in my search for the females 

 of Labidocera magna, I found in the same bottle two other 

 species. The first is an aberrant species of Pontella, Dana, agree- 

 ing with that genus in the number of eyes, but ven*- nearly re- 

 sembling Labidocera Darwinii in the structure of the right male 

 antenna, and is therefore a link between these two genera. The 



