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Show 1895.] MB. F. E. BEDDAED ON NEW EAETHWOBMS. 235 sac of penial setae. At the external orifice it widens out into a sac of which the epithelium is more glandular on the ventral surface, being here composed of tall non-staining cells; from this sac a tube lined with a precisely similar epithelium leads to the exterior. Hab. St. 140, Uschuia, forest. The most singular feature in the internal organization of this worm is the ovaries : these are positively of enormous size. They are quite as large as the sperm-sacs of the same worm, aud occupy a considerable amount of the coelomic cavity of their segment (the xiiith). Not only are the ovaries themselves thus unusually large- the ova share in the increased size, but although they are very much larger than the ova of the common Earthworms of this country, they do not approach in any way the ova of tbe aquatic Oligochaeta: that is to say, they have not got a great amount of yolk deposited within them-no more, in fact, is present than in other Earthworms. So large are the ova that they are not merely visible to the unarmed eye-this is possible even in the common Allolobophora-but they suggest parasitic Gregarines, with which I was disposed to identify the ova until they were submitted to microscopic examination. The spermathecae are in the ixth segment, as is almost invariably the case with this genus. A stalked diverticulum opens in common with an oval pouch; the diverticulum has a mulberry-shaped outline, and appears, as in other worms, to be the only receptacle of the sperm. The minute structure of this diverticulum is also different from that of tbe pouch : when sections are taken through the periphery it presents the appearance of a compound tubular gland, the tubes being separated from each other by interstitial tissue. The whole diverticulum in fact consists of a much-folded epithelium. (6) Microscolex corralensis, n. sp. Of this apparently new form I only found a single species in a copious gathering from Corral, Valdivia. Its length is 40 mm., the diameter 4 m m . ; the number of segments a little over 70. In the preserved state this worm is a pale greyish brown, the clitellum being pinky brown. The prostomium is continued by furrows over the entire buccal segment: these furrows converge posteriorly but do not meet. The clitellum occupies segments xiii.-xvii., the posterior part of xiii. and the anterior part of xvii. not being invaded by glandular substance. On xii. and xiv. alone the clitellum is complete; on the remaining segments it only reaches the veutral pair of setae. The setae are strictly paired from end to end of the body. On the segments immediately in front of and behind the xviith (which bears the male pores) the ventral pairs diverge from each owing to the tension caused by the rather lateral position of the male pores. There are dorsal pores, but I a m unable to fix the exact segment in which they commence. Some of the segments in the neighbourhood of the spermathecae |