ON THE BRITISH ANNELIDA. 259 



About many of the foregoing observations cited on the authority of Mr. 

 Brightwell, there is an air oi a priori improbability. They certainly cannot 

 be admitted in science until confirmed by other observers aware of the ana- 

 tomical discoveries announced in this memoir. Since each ovario -uterine 

 organ has its own oviduct through which it extrudes its ova, it is reasonable 

 to suppose that these ova, when extruded, would not be found as a defined 

 ring-like mass encircling the mid-region of the body as commonly stated, 

 and which is said to be thrown off by violent efforts on the part of the ani- 

 mal, the body being withdrawn from within it. A sort of cocoon, open at 

 both extremities, is said thus to be produced, which contains from twelve to 

 fourteen ova, enclosed in a protecting substance furnished by the mucous 

 glands of the parent ; and the young, after their escape from the ova, quit 

 the cocoon through the openings left by its body. It must be repeated that 

 all this account requires to be confirmed by a trustworthy observer. 



The author has been more fortunate in unravelling the reproductive ope- 

 rations of the Earth-worm. Between this worm and the Leech there exists a 

 most remarkable resemblance as regards the structure and distribution of the 

 utero-ovarian system. In Lumbricus however one prominent and essential 

 point of difference is at once observed. Here the testicular bodies are 

 arranged in a longitudinal series as in the Leech, but concentrated into a 

 considerable glandular mass around the cesophagus and in front of the giz- 

 zard. It is quite evident from this arrangement that a bisection transversely 

 of this worm would leave two halves, both of which would be wanting in a 

 paramount constituent of the organism. 



Before proceeding to describe the results to which the author has been 

 led by his recent investigations into the anatomy of the Earth-worm, it is 

 desirable, first, to present a summary of what has been taught on this subject 

 up to the date of the present Report. Mr. Rymer Jones observes*, " Few 

 points connected with the history of the Earth-worm have given rise to so 

 much speculation as the manner of their reproduction. The generative 

 organs have long been known to be lodged in the anterior part of the body, 

 their position being indicated externally by a considerable enlargement or 

 swelling which extends from the seventh to about the fourteenth "segment, 

 counting from that in which the mouth is situated. On opening this portion 

 of the animal, a variable number of white masses are found attached to the 

 sides of a crop and gizzard, which have long, by general consent, been looked 

 upon as forming the reproductive system ; some having been regarded as re- 

 presenting the testes, others as the ovaria ; yet so delicate are the connexions 

 which unite these glandular masses, and such is the difficulty of tracing the 

 ducts by which they communicate with the interior of the body, that the 

 functions to which they are individually appropriated have given rise to 

 much discussion. The Lumbrici have been generally acknowledged to be 

 hermaphrodite, that is, possessed of organs adapted both to the formation 

 and the fertilization of the ova ; and it is likewise well understood that the 

 congress of two individuals is essential to the fecundity of both, as in the 

 earlier months ; the mode in which they copulate is a matter of constant ob- 

 servation. At such times two of these animals are found to come partially 

 out of the ground from contiguous holes, and applying together those seg- 

 ments of their bodies in which the generative organs are situated, are ob- 

 served to remain for a considerable time in contact, joined to each other by 

 a quantity of frothy spume which is poured out in the neighbourhood of the 

 sexual organs. No organs of intromission, however, have ever been distin- 

 guished, neither until recently had the canals communicating between the 

 * Op. cit, p. 207. 



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