ASCAKIS LUMBRICOIDES. 159 



(424.) It would seem that the food of these Entozoa, being already 

 ardmalized by having undergone a previous digestion, requires little 

 further preparation ; and we are not surprised at finding, in the gene- 

 rality of the Coelelmintha, no accessory glandular apparatus appended 

 to the digestive canal for the purpose of furnishing auxiliary secretions. 

 In two species only have tributary secreting organs been detected. In 

 one example, GnatJiostoma aculeatum (Owen), found in the stomach of 

 the tiger, and which is remarkable as possessing a pair of rudimentary 

 jaws, four elongated cseca are appended to the mouth, into which they 

 pour a fluid, analogous, no doubt, to that of the salivary glands* ; in a 

 species of Ascaris, found in the stomach of the dugong, Professor Owen 

 likewise discovered a caecal appendage opening into the alimentary tube, 

 at some distance from the mouth, and which, without much stretch of 

 imagination, might be regarded as the first and simplest rudiment of a 

 biliary system t. 



(425.) In further prosecuting our inquiries concerning the process of 

 nutrition in these Entozoa, we must now speak of a peculiar structure, 

 first noticed by CloquetJ, and apparently intimately connected with the 

 assimilation of nutriment. Projecting from the inner surface of the 

 abdominal cavity, especially in the dorsal and ventral regions, there are 

 a great number of gelatinous, spongy processes (appendices nourriciers}, 

 which, although they have no apparent central cavity, would seem to 

 be appended to vascular canals seen upon the lateral aspects of the 

 body : it is probable, therefore, that their office is to absorb the nutri- 

 tive juices that exude through the delicate walls of the intestine 

 and convey them into the circulatory apparatus; or they may be 

 reservoirs for nourishment, analogous to the adipose tissue of higher 

 animals. 



(426.) In the Coelelminilia the sexes are separate ; and the generative 

 organs, both of the male and female, exhibit great simplicity of struc- 

 ture. In the female Ascaris, the aperture communicating with the 

 ovigerous apparatus is placed upon the ventral aspect of the body, a 

 little anterior to the middle of the worm (fig. 78, 1, m). This opening 

 leads to a wide canal (I), usually called the uterus ; and from the last- 

 mentioned organ arise two long and undulating tubes, which, dimi- 

 nishing in size, run towards the posterior extremity, where they become 

 completely filiform, and, turning back upon themselves, are wound in 

 innumerable tortuous convolutions around the posterior portion of the 

 alimentary canal, until the termination of each becomes nearly imper- 

 ceptible, from its extreme tenuity. In these tubes, which, when unra- 

 velled, are upwards of 4 feet in length, the ova are formed in great 

 numbers, and are found to advance in maturity as they approach the 



* Owen, Proceedings of the Zoological Society, Nov. 1836. 



t Preparation No. 429 A, Mus. Coll. Surg., Phys. Catalogue, p. 121. 



| Anatomie des Vers intestinaux. Paris, 1824. 



