SOME OBSERVATIONS ON NEMATOIDEA IMPERFECTA. 243 



Passali, but not a trace of it was to bo found; the cloaca yet contained one or two frag- 

 ments of the skeleton of the Passulus, with some epithelial scales, mucus, and a dark, mud- 

 like, granular matter, but nothing else. The entozoon had been digested with the soft 

 parts of the insect. 



Two days after, I killed the remaining frogs, but in none did I discover the slightest 

 trace of the entozoon in question. From the results thus obtained, we may conclude that 

 this parasite finds no condition favourable to its existence, leaving out of the question 

 entirely any farther development, in frogs, or probably in any reptile. Hut still the ento- 

 zoon may pass part of its existence in other animals. In a state of nature, frogs would 

 rarelv have a chance of feasting upon Passalus* because the latter is found in forests, 

 beneath bark and in the wood of decaying dead trees, and here the woodpecker (I'ieus,) 

 or other insectivorous birds would be most likely to meet with it, and with such birds a 

 similar experiment, to the one performed with frogs, might be tried to see if the develop- 

 ment of the entozoon would not advance within them. 



2. NematoiSeum thoracis cavitaits Passali cornuti, (pi. 11, fig. 4G.) — This is an anguillula- 

 likc worm in an imperfect condition, found occasionally in the cavity of the thorax of 

 Passalus cornuius. It resembles an embryonic Ascaris. Its movements are active and 

 wriggling. It is whitish, translucent, cylindrical, and attenuated and acute posteriorly. 



Structure. — Integument transparent, and colourless. (Esophagus long, narrow, cylindrical, 

 and faintly outlined. Intestine broad, cylindrical, granular in appearance and faintly out- 

 lined. Anus an oblique fissure, not very distinct, just in advance of the tail, which latter 

 is short and acute. 



Length, l.GGth in.; breadth, 1.1000th in. 



3. Nematoideian inleslinorum Armadillonis jnllularis, (pi. 11, fig. 47.) — This is also an 

 anguillula-like entozoon, found coiled up and adhering by ihc mquth to the epithelial layer 

 of tin' intestine of Armadillo pillularis. It is white, cylindrical, attenuated, and acute pos- 

 teriorly. The intestinal canal presents the same appearance as in the last, but the oeso- 

 phagus is broader. 



Ijength, 1.53d in.; breadth, 1.360th in. 



4. Ncmatoidciim intcgumenti Lumbriculi limosi, (pi. 11, fig. 48.) — This is a small ento- 

 zoon which I found, six in number, doubled up and motionless, contained in transparent 

 oval cysts, imbedded in the integument of the 9th, 11th, and I5tb, annuli of a Lumhri- 

 culus limosus. It resembled an embryo within an ovum. Its form is cylindrical, subacute 



teriorly, truncated anteriorly, colourless and transparent. No interior organs were 

 observable, except a small, round, transparent corpuscle posteriorly, and anteriorly, a pro- 

 boscidiform body, partly projecting from the anterior extremity. 

 Length, 1.560th of an inch. 



I be habitation ni I however, offers no reason why a frog or toad should not occasionally feast upon them. 



Atone time I thought the insect was confined to the haunts in which it is usually found, but it undoubtedly flies 

 at night, as I ha i in places where some days before they did not exist, and mv lal I Dr. Bee Kern, 



once brought me half a pint of this insect,, which he obtained on the Atlantic ocean, a few miles from shore, vt iih nu. 

 merous other insects, one morning after there had been a busk wind in the night. 



