of the ^British Sesstle-eyed Crustacea.^ 473 



the immature male. It certainly comes very iu:ir P. Ilird- 

 vmni (Walker) [ = /*. odontotvjx (Sars)], and 1 have a 

 specimen wjiich cannot be tlistint]jui.shcd from a young male 

 P. falcdtus, but which i)a.s the last two joints of the upper 

 anteniife clothed with the dense j)lumo3e setie which are held 

 to be characteristic of sexual maturity in the male. As 

 regards the tooth on the finger of the second gnathopods of 

 P. Jlerdmant'j two of the above three specimens have it, while 

 the third, like them in other respects, has not ; so that it 

 seems to be a variable character. I am disposed to consider 

 P. Jlerdmani and P. pusillus (Sars) as examples of arrested 

 development and mere varieties of P. falcatus. 



Podocerus pelagicus (Leach). Not in the collection. 



No doubt, as suggested by Normau, the female of P. fal- 

 catus. 



Podocerus ocius (Bate). Not in the collection. 



The specimen described is probably a female. This species 

 has lately been described by Delia Valle. I have specimens 

 from Port Erin, Isle of Man. The male has the tooth at the 

 base of the palm longer than the central tooth. 



Cerapus ahditus (Templeton) and C. difformis (M.-Edw.). 

 Now Erichthonius ahditus and E. difformis. 



Dercotho'e punctatus (M.-Edw,). Not in the collection. 

 Is Erichthonius difformis female, according to Norman. 



Siphonoecetes typicus (Kroyer). One specimen. 



Apparently S. CoUetti (Boeck). S. typicus (Kr.) is an 

 Arctic species, not even found on the Norwegian coasts. The 

 species, however, seem to be barely distinct. 



Siphonoecetes Whitei (Gosse) . Not in the collection. 



Siphonoecetes crassicornii ? (Bate). 

 Now Cerapus crassicornis. 



Ncenia tuberculosa (Bate). 

 Now Podoceropsis sophice (Boeck). 



Ncenia rimapalmata (Bate) and iV. excavata (Bate). 

 Respectively male and female of the same species, and 

 Ann. (i: Mag. X. Hist. Ser. 6. Vol. xv. 33 



