44 Dr. E. P. Wright on a new Species q/'Pennella. 



difficulty chiefly arises from the fact that all the organs of these 

 strange, grotesque creatures are subject to such wondrous 

 transformations. Such a division, for example, as that of 

 Milne-EdAvards * into those having a head with two horns 

 and those having a head with three, disappears before such a 

 species or variety as the P. varia7is, St. & L.f Heller, in the 

 * Novara-Reise '|, divides the family Lernaeid^ into two groups 

 or subfamilies, the second of which is distinguished by the 

 females having filiform ovisacs : this section he calls Pennel- 

 linse, subdividing it as follows : — 



I. Those with a rostriform mouth, ovisacs long and not con- 



voluted, bodies covered with a thin integument. 



II. Those with a non-rostriform mouth, ovisacs convoluted, 



bodies covered with a hard integument. 



The genera placed in the first division are : — Pennella, Oken; 

 Peniculus, ^ovdmanri] Lernceonema, M.-Edw. ; and Perodermay 

 Heller. 



Pennella sultana, Nord., is placed by Heller § in the second 

 division, and forms a new genus, LernceolojyJiuSj which, so far 

 as regards the possession of abdominal plumose appendages, 

 takes the place in this division that Pennella does in the first 

 division. 



While, therefore, fully aware of the difficulties that for the 

 present surround this question of classification, and ready to 

 admit that neither length of body nor size of cephalic, thoracic, 

 or abdominal appendages can be looked on as certain indica- 

 tions of specific differences, I yet venture to bring forward as 

 new the following species, in the belief that it is undescribed, 

 and with the hope of throwing some little light on our know- 

 ledge of the genus. These parasites do not occur so very 

 frequently as to lead me to hope that by waiting I might be 

 able to decide the questions as to its range of variation &c. 

 thoroughly. 



Pennella orthagorisci, sp. n. 



? . Cephalic region. Twice as broad as long, divided into two 

 lobes. On its dorsal surface, and situated between these lobes, 

 an eye-spot ; on either side of which, but scarcely in front, a 

 pair of minute antennules with from thirteen to fifteen longish 

 setse on each ; still further in front a pair of antennaj obscurely 



* ' Histoire Naturelle des Crustac^s,' tome iii. p. 522. 

 t i.e. p. 413. 



X Zoolo^scher Theil, Rd. ii. Abth, 3. Crustaceeu bescliriebeu vou (', 

 Heller. Wien, 18G5, p. 244. 

 § L.c. p. 2ol. 



