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B.A., of Port Chalmers, N.Z. The animals are devoid of eyes, completely 

 destitute of pigment, and of comparatively large size, the largest being nearly 

 IV2 inches long. — III) A new genus of the Temnoceplialeae. Temnocephala 

 is such an aberrant member of the Platy helminthes that the discovery of a 

 related form is of considerable interest. In Temnocephala there are at the 

 anterior end of the body a number (four to six) of long slender tentacles ; at 

 the opposite end a large ventral sucker. In the new genus, which it is pro- 

 posed to call Actinodactyli(s , twelve or fourteen tentacles are present distri- 

 buted along the lateral ;nargins of the body and radiating outwards from it. 

 A ventral sucker occupies the same position as in Temnocephala. Eyes are 

 completely absent ; but in most other respects the resemblance to Temnoce- 

 phala is fairly close. The new form occurs in the branchial cavities of Eii- 

 gaeus fossor, the burrowing land-crayfish of Gippsland. — 4) Some points in 

 reference to the muzzle of Ornithorhynchus . By J. T. Wilson, MB., Pro- 

 fessor of Anatomy in the University of Sydney, and C. J. Martin, M.B., 

 B.Sc. , Demonstrator of Physiology in the University of Sydney. The so- 

 called »duck-bill« is correctly described by Huxley (Anat. Vert.) as a »flatte- 

 ned muzzle resembling the bill of a duck«, but the integument covering it is 

 not »leather)'«, as he terms it, and as Owen (Anat. Vert.) also regards it, and 

 certainly not »horny« as Flower (Osteol. Mamm.), Mivart and other authors 

 of repute describe it. It is, on the contrary, »uniformly smooth and flexible«, 

 as Waterhouse styles it (Nat. Hist. Mamm.), but not specially »thick«, as 

 his description would lead one to suppose. The osseous skeleton of the jaws 

 is correctly described by most of the authors consulted, but the cartilaginous 

 basis of the lips forming a marginal extension of the skeleton of both upper 

 and lower jaws, though noticed by Meckel and Owen in particular, is igno- 

 red by some writers ; and, so far as the authors know , its real significance 

 in the morphology of the skull of this animal has been entirely overlooked. 

 W. K. Parker (Mamm. Desct.) has given ample recognition to the arrange- 

 ment in question, but he leaves it doubtful whether the corresponding car- 

 tilage in the lower lip is or is not the representative of part of the slab of 

 cartilage upon which the dentary has grafted itself. This doubt may be 

 disposed of by the statement that the cartilaginous basis in the lower lip, 

 though analogous in position and function to that in the upper, differs from 

 the latter essentially, in that it is composed, not of true hyaline cartilage, 

 but of fibro- cartilage, and hence it probably possesses no special significance 

 in the morphology of the skull. The marginal strip or sheet of true hyaline 

 cartilage in the upper lip, however, has a probable meaning altogether diffe- 

 rent from that suggested by Parker. The authors find that in the adult 

 animal, which alone they have had the opportunity of examining, the mai"- 

 ginal cartilage of the upper lip is a forward lateral growth and expansion 

 of an area of cartilage which fills up that gap in the palate left between the 

 separated maxillae and premaxillae , and which is itself continuous behind 

 with the true cartilaginous nasal septum, and is therefore to be looked upon 

 as a true prenasal element in the axial cranial skeleton. The so-called 

 dumb-bell shaped bone has been regarded by some authors as a pre-nasal 

 bone, but Albrecht and Turner (Journ. Anat.) have shown, and Sym- 

 ington Troc. Zool. Soc.) has confirmed the conclusion, that it is really a 

 membranous ossification corresponding to the mesial osseous centre of the 

 premaxilla of other mammals. But none of the authors mentioned seems to 



