RESEARCHES IN HELMINTHOLOGY AND PARASITOLOGY. 217 



organs were observable. At the middle of the posterior portion of 

 the body, in the usual position of the testes, there appeared a single 

 clearer spot, and in advance of it a clearer streak. The character 

 of these he had not determined. 



Many worms, the Echinorhynchus proteus, clung to the interior of 

 the intestine its whole length, but they were not so numerous as nor 

 larger than they are commonly found to be in smaller individuals of 

 the same fish. 



Of two other large Rock-fish examined, weighing each about a 

 dozen pounds, one was free of parasites of all kinds, and in the 

 other there were only a few of the little crustacean, Ergasilus, adher- 

 ing to the gills ; and within the abdominal cavity, adherent to the 

 stomach, closely coiled and encj'sted, a dozen nematoid worms, the 

 Agamonema capsiilaria, a common parasite of the shad and herring. 

 Neither of the fish contained a sitigle Echinorhynchus, a remarkable 

 circumstance, for he had never before examined a Rock-fish without 

 finding this parasite present. 



[May, 1888. No. 564. See Bibliography.] 



Louse of the Pelican. — Prof. Leidy remarked that the admirable 

 monograph of E. Piaget, " Les Pediculines," a large work, with 

 supplement, in three quarto volumes, illustrated, and published in 

 Ley den from 1880 to 1885, presented tonight, had reminded him 

 that he had formerly made a communication to the Academy on an 

 insect of the kind, which was remarkable on account of its living in 

 the pouch of the Pelican. A brief description of the louse, under 

 the name of Menopoji peralc, is given in the Proceedings, 1878, p. 100. 

 Mr. Piaget describes two species of Menopon from Pelicans, M. titan, 

 living on Pelicanus oiiocrotahis and M. consanguineum, which he ob- 

 serves appears by preference to infest the interior of the great pouch 

 of P. ervthrorhynchus. He remarks of the latter that it probably has 

 some relation with Menopon peralc, and regrets the insufficient de- 

 scription of this species for comparison. Prof. Eeidy continued that 

 M. Piaget's figures of Menopon titan and M. consangidncuvi appear 

 so nearly alike and resemble so closely M. perale that from his own 

 judgment he would have regarded them as all of one species. In 

 1878 he had prepared a more detailed description, with figures of 

 Menopon perale, intended for publication in one of the Government 

 reports, but, as it was not called for, it was forgotten until he was 

 reminded of it by the appearance of the great work of M. Piaget. 

 Menopon perale was named from specimens submitted to him by 

 Prof. Wyman, who obtained it from the pouch of Pelicanus trachyrhyn- 



