532 ANNULOSA, OR WORMS. 



orifice, seems to be properly a parasite in the intestines of water 

 insects ; but it is frequently found in large knot-like masses 

 (whence its name) in the water or mud of the pools inhabited 

 by such insects, and may apparently be developed in these 

 situations. The Anguilluloe are little eel-like worms, of which 

 one species, A. fluviatilis, is very often found in fresh water 

 amongst Desmidiece, Confervoe, &c., also in wet moss and moist 

 earth, and sometimes also in the alimentary canal of snails, 

 frogs, fishes, insects, and larger worms ; whilst another species, 

 A. trtiiei, is met with in the ears of wheat affected with the 

 blight termed the "cockle;" another, the A. glutinis, is found 

 in sour paste ; and another, the A. aceti, was often found in 

 stale vinegar, until the more complete removal of mucilage and 

 the addition of sulphuric acid, in the course of the manufacture, 

 rendered this liquid a less favorable " habitat" for these little crea- 

 tures. A writhing mass of any of these species of " eels," is one 

 of the most curious spectacles which the Microscopist can exhibit 

 to the unscientific observer ; and the capability which they all 

 possess (in common with the Rotifera and Tarcligrada) of revival 

 after desiccation, at however remote an interval, enables him to 

 command this spectacle at any time. A grain of wheat within 

 which these worms (often called vibriones] are being developed, 

 gradually assumes the appearance of a black pepper corn ; and 

 if it be divided in two, the interior will be found almost com- 

 pletely filled with a dense white cottony mass, occupying the 

 place of the flour, and leaving merely a small space for a little 

 glutinous matter. The cottony substance seems to the eye to 

 consist of bundles of fine fibres closely packed together ; but on 

 taking out a small portion, and putting it under the microscope, 

 with a little water under a thin glass cover, it will be found 

 after a short time (if not immediately) to be a wriggling mass of 

 life, the apparent fibres being really Anguillulce, or the " eels" 

 of the Microscopist. If the seeds be soaked in water for a 

 couple of hours before they are laid open, the eels will be found 

 in a state of activity from the first ; their movements, however, 

 are by no means so energetic as those of the A. glutinis or 

 " paste-eel." This last frequently makes its appearance spon- 

 taneously in the midst of paste that is turning sour; but the 

 best means of securing a supply for any occasion, consists in 

 allowing any portion of a mass of paste in which they may pre- 

 sent themselves, to dry up, and then, laying this by so long as it 

 may not be wanted, to introduce it into a mass of fresh paste, 

 which, if it be kept warm and moist, will be found after a few 

 days to swarm with these curious little creatures. 



360. Besides the foregoing orders of Entozoa, the "trema- 

 tode" group must be named; of which the Distoma hepaticum, or 

 "fluke," found in the livers of sheep affected with the " rot," is a 

 typical example. Into the details of the structure of this animal, 

 which has the general form of a sole, there is no occasion for us 



