INFUSORIA. 23 



Anentera (without intestines). 



Monas lens, Müller {pi 75, Jig. 1), is about -g-iöth of a line long. The line 

 used in Natural History is the twelfth part of a French inch. 



Vibrio anguillula {pi. 75, Jig. 7). This active species, which bears some 

 resemblance to an eel, is found in vinegar and in sour paste, and can be 

 revived after having been desiccated. It is by some placed among the 

 worms, while Dr. Joseph Leidy, a distinguished comparative anatomist of 

 Philadelphia, thinks their nature may be vegetable. His remarks, some- 

 what condensed, are as follows : 



" Even those moving filamentary bodies belonging to the genus Vibrio. 1 

 am inclined to think, are of the character of algous vegetation. Their 

 movement is no objection to this opinion, for much higher confervae, as the 

 Oscillatorias, are endowed with inherent power of movement, not very 

 unlike that of the Vibrio. . . In the stomach and small intestine of the 

 toad, £tcfo americmmis, there exist simple, delicate, filamentary bodies. One 

 is exceedingly minute, forms a single spiral, is endowed with a power of 

 rapid movement, and appears to be the Spirillum undula of Ehrenberg ; 

 the second is an exceedingly minute, straight, and short filament, with a 

 movement actively molecular in character, and is probably the Vibrio 

 Uneola of the same author ; the third consists of straight, motionless 

 filaments, measuring xtVs i^c^^ long, by js.otö broad ; some were, how- 

 ever, twice, or even thrice this length, but then I could always detect 

 one or two articulations, and these, in all their characters, excepting want 

 of movement, resemble the Vibrio. In the rectum of the same animal, the 

 same filamentary bodies are found, with myriads oi Bodo intestinalis i but 

 the third sj)ecies, or longest of the filamentary bodies, have increased 

 immensely in number, and now possess the movement peculiar to the 

 Vibrio Uneola, which, however, does not appear to be voluntary, but 

 reactionary ; they bend and pursue a straight course, until they meet with 

 some obstacle, M^hen they instantly move in the opposite direction, eithei- 

 extremity forward. But it must not be understood that these facts militate 

 against the hypothesis of the production of contagious diseases through the 

 agency of Cryptogamia. It is well established that there are microscopic 

 Cryptogamia capable of producing and transmitting disease, as in the case of 

 the Muscardine, &c." — Proceed. Acad. Nat. Sei. for October, 1849. 



Vibrio tritici, which infests wheat, has been revived by moisture after 

 being in a dry condition for six years. 



Gonium pectorale {pi. 75, ßg. 11, enlarged) is an interesting species, 

 resembling a table-shaped mass, in which there are about sixteen green 

 animalcula. When abundant they give a green color to the water. 



Volvoxglobator{ßg. 15, enlarged) was discovered by Leeuwenhoek in 169S. 

 and is abundant in stagnant water. It is globular, of a pale-green color, 

 and from one third to a sixth of a line in diameter. The surface is finely 

 reticulated and provided wäth vibrillae, by means of which it advances 

 slowly through tlie water with a revolving motion. The Volvox is 



227 



