IN THE BODIES OF ANIMALS. 383 



ther is added concerning it, or the mode in which he dis- 

 covered it, the observation of such a man, unknown to Helmin- 

 thologists, cannot be of itself sufficient to establish the fact: 

 whether he mistook the Planaria lactea, or the common 

 ligula of fish, for the Tcenia, cannot be positively asserted. 



Unzer remembers to have seen the Tcenia in a well. Tissot 

 likewise asserts, that a Tcenia he had found in a similar situa- 

 tion, corresponded with that found in man ; the former, how r 

 ever, on being questioned by O. Fr. Muller on the Tcenia he 

 had discovered, said that it was only a portion about an inch 

 long, which may have been digested by a man or fish, and 

 carried into the well by accident ; and this was actually the 

 case in the instance of Tissot. But even Gmelin, as we 

 learn from Pallas, declared that he had himself once doubted 

 whether the eggs of frogs, linked together, were not a new 

 species of Tcenia. The illustrious Muller, whilst travelling 

 on the confines of Suecia, having been assured that a certain 

 river abounded with Taeniae, made a search accordingly. He 

 drew out masses of dead entangled Taeniae, and with them 

 (a fact which explains the circumstance) a quantity of the 

 intestines of fishes, which the fishermen were in the habit of 

 throwing into the water. As the Tcenia was found in the river 

 dead, we cannot conclude that this was the place of its birth. 



Bremser found Ascarides lumbricoides at all periods of the 

 year in water, which he drew from the well of Ccenubus Divus 

 Ludgerus, in which he could find neither fish nor any living 

 creature, from the bodies of which they could have been ex- 

 creted. He found these same worms not only at Helmstad, 

 but also in spring water near Ballenstad, in the beginning of 

 December 1772. These white Ascarides were about three 

 lines in length, never so much as four, and of the thickness of a 

 slender thread; but he had observed that the mouth was furnished 

 with three distinct nodules, and by the assistance of a micro- 

 scope, he perceived, in the midst of these a tubule, so that 

 there could be no doubt as to the species. He inferred, that 

 by drinking this water, the worms would be carried into the 

 body, and by being nourished, become larger. Now, if the 

 observation of Bremser had led him to the opinion that the 

 worm in question was an Ascaus, still I cannot understand 

 why he should have regarded it as the young of the A. lum- 

 bricus, and not rather that of the A. vermicularis, and the 



