CRUSTACEAN PARASITES OF FRESH-WATER FISHES. 665 



a short but distinct petiole. Ova sacs nearly as long- as or considerably 

 longer than the body, linear, with three or four trausv^erse and eighteen 

 to thirty-five longitudinal series of eggs. 



The antennulsB are much longer than in the species just described, 

 extending fully as far forward as the mouth. The autennne are propor- 

 tionally rather larger than in either of the species here described, but 

 are similar to them in structure. The palpi are small, and each one is 

 terminated by two minute, papilla like appendages. The mandibles 

 (fig. 17, 6, c) each have four stout distal teeth, besides a smaller terminal 

 one, which is nearly obsolete on one mandible and conspicuous on the 

 other, and three small proximal teeth on one and two on the other. 



Entire length of a specimen, from mouth to extremities of ova-sacs, 

 IS""" ; length of body, S^^'.S ; diameter of body, I'^^.S ; length of ova- 

 sacs, 6""" ', diameter of ova-sacs, 1""". 



Found by Mr. J. W. Milner on the white-fish (Coregamts albus) at 

 Ecorse, Mich., and at Outer Island, Lake Superior. 



This species is probably not a true Lerricvopoda, and is perhaps the 

 representative of an undescribed genus. 



Cauloxenus stygius Cope. 



Proceedings Academy Nat. Sci. Philadelphia, 1871, p. 297 ; American Natiiralist 

 vol. vi, pp. 420, 412, tigs. 111-113, 1872, and reprinted in Third and Fourth 

 Annual Reports of the Geological Surveyof ludiana, pp. 175, 164, 1872; Packard 

 Fifth Annual Report Peabody Academy of Science, Salem, j). 94, 1873. 



This is a peculiar lernfean, described by Professor Cope as parasitic 

 on the blind fish {AmMyopsis) of Wyandotte Cave, Indiana ; also from 

 a cave in Bradford, Orleans County, Ind., according to Professor Pack- 

 ard. According to Professor Cope, it is allied to Achtheres and Lenice- 

 opoda, although the arms by which the animal is attached are united 

 for their whole length, and it is stated that it " is not a sucker or 

 devourer of its host, but must feed on the substances which are caught 

 by the blind fish and crushed between its teeth"! 



Family Lern^ocerid^. 



Lern^ocera cruoiata Lesueur. 



Lerneoeera cruoiata Lesueur, Journal Academy Nat. Sci. Philadelphia, vol. iii, 



286, pi. 11, fig. 4, 1824; Edwards, Hist. Nat. des Crustac6s, vol. iii, p 527. 

 Lernea cruciata DeKay, Nat. Hist, of New York, Crustacea, p. 59, 1844. 



On Centrarchus (vneus in Lake Erie, according to Lesueur. 

 Lern^ocera Catostomi Kroyer. 



Bidrag til Kundskab om Snyltekrebseue, p. 321, pi. 18, fig. 4, 1863. 



Described by Kroyer as found in the Mississippi River, at Saint Louis, 

 on Gatostomus niacrolepidotus, and so is very likely to be found much 

 farther north and east. 



Another species is described by Kroyer, {L. Pomotidis, op. cit., p. 323, 

 pi. 15, fig. 5,) from a species of Pomotis taken at New Orleans. 



