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Show 302 MR. F. E. BEDDARD ON NEW OR [May 18, about five or six segments from its commencement, the intestine undergoes a remarkable change in its structure ; in three or four segments the walls of the intestine are greatly thickened, but these specially thickened regions are separated by intervals where the intestinal walls have preserved their normal delicacy of structure ; these intervals are on either side of the septa. These appearances, which recall the moniliform structure of the oesophagus in Monili-gaster, can hardly have been brought about by the effects of the alcohol in which the specimens were preserved. There were no caeca present, unless these local thickenings represent the caeca morphologically ; in other Perichcetce the caeca generally contrast with the intestine by their greater thickness. On several of the anterior mesenteries were bunches of glandular tubules similar to those found in other Perich&tce, and wbich may represent the nephridia. The foregoing brief description is, I think, enough to distinguish this species from any that is at all sufficiently known. 3. A NEW SPECIES OF EUDRILUS (Eudrilus boyeri). Among some Earthworms kindly sent to me from New Caledonia by Mr. Layard were about a dozen individuals which I refer to Perrier's genus Eudrilus K This genus is already known to inhabit South America and the West Indies, but has not been recorded from anywhere else. I am inclined myself to suspect that the New- Caledonian specimens may have been accidently imported, and may not be indigenous to that island. I name the species after M . Boyer of N e w Caledonia, who collected the specimens for Mr. Layard. At the same time I am not convinced that the species really is new. It appears to differ from all the three species described by Perrier in the long coiled oviduct, and in the termination of the vasa deferentia at the middle of the prostate gland. With regard to the first mentioned point of difference, I have elsewhere 2 expressed the opinion that M . Perrier has mistaken the relation of the ovary to the spermatheca. The oviduct in m y specimens so unmistakably corresponds to what Perrier has described as a diverticulum of the spermatheca, that I cannot but think that they are really identical even if the species are distinct. M. Perrier did not make use of the method of section-cutting, which is so infinitely better than dissection for deciding an anatomical relation like that of the ovary and its duct. Still the difference between m y species and his in respect of the vasa deferentia makes me hesitate in asserting that his conclusions are mistaken. With regard to the vasa deferentia, M . Perrier states that in his species they open directly into the bursa copulatrix, and not indirectly by way of the prostate gland as in Eudrilus boyeri. With M. Perrier's figure before m e it appeared to me that in one instance, at any rate, Eudrilus boyeri agreed with Eudrilus decipiens ; but in two or three other specimens which I dissected the vasa 1 Nouv. Arch. d. Museum, t. viii. (1872) p. 71. 2 Proc. Eoy. Soc. Edinb. (forthcoming paper); Zool. Anzeig. Bd. ix. (1886) p. 342. |
