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Show 698 MR. F. E. BEDDARD ON NEW [Dec. 20, no cell-outlines visible, but nevertheless I cannot but regard the mass as being composed of cells with perhaps very thin boundary lines. In the centre of each of these glands was a darkly staining rod of tissue which appears to be a blood-vessel; at the apex these glands opened into the lumen of the oesophagus by an exceedingly narrow diverticulum of the oesophagus; this tube- soon ends, leaving the greater bulk of the calciferous gland composed of the peculiar tissue that I have already described. The only other Oligochaets in which calciferous glands at all comparable to these exist are the genera Gordiodrilus and Trichochceta. I have lately l described the principal anatomical characters of the former new genus, which is mainly found in tropical Africa, though also extending its range to the N e w World. In all the species of that genus there is a single unpaired median pouch in the ninth segment which in certain particulars resembles the calciferous glands of Eudriloides durbanensis ; the resemblance consists in the tissue which builds up the greater part of the gland and which is apparently identical with that which builds up a greater proportion of the glands in Eudriloides. The peculiar kind of tissue which characterizes the calciferous glands of these two genera of Oligochaeta is, however, not unknown in the group; in several aquatic Oligochaeta, for example in some Naids and in many Lumbriculidae such as Sutroa2, the nephridium, just after traversing the septum, is swollen out into an oval tract which shows precisely the same structure as that of the glands already described. I have figured this tissue in the American Lumbriculid Sutroa, and suggested that it might possibly serve as a filtering tissue. The oval swelling is permeated by fine canaliculi which are not always apparent; in the same way the similar tissue in the calciferous glands of Eudriloides and of Gordiodrilus seems to be traversed by fine canaliculi (shown in the case of Gordiodrilus in fig. 8 of plate vii. of my memoir already quoted dealing with the anatomy of that worm). It is quite possible, therefore, that Michaelsen's notion that these glands serve as organs of assimilation, rather than as organs of secretion, may prove to be correct in the two Annelids which possess this peculiar form of calciferous gland ; although, as I have pointed out, there can be no doubt that the ventral pouches of Eudrilus do not, at any rate, entirely serve such a purpose, for I found particles of calcareous secreted matter in the lumina of the said pouches; furthermore the resemblance of this tissue to that found in the nephridia is worthy of note in relation to the fact that in Gordiodrilus there appears to be a communication between the ventral pouches and the nephridia. I do not, however, wish to insist upon more than the actual structural likeness between the tissue in the two series of organs; this is indeed very striking. It may be that this resemblance between the calciferous pouches of Eudriloides and Gordiodrilus is some evidence 1 " On a new Genus of Oligochaeta &c," Ann. & Mag. Nat. Hist. ser. p. 74 (1892). 2 " A Contribution to the Anatomy of Sutroa," Tr. Boy. Soc. Edinb. (to appear immediately). r |