47 

 2. Linnean Society of New South Wales. 



November 27th, 1895. — 1) On some Developments of the Mammalian 

 Prenasal Cartilage. By R. Broom, M.B. , CM., B.Sc. The comparative 

 anatomy of the prenasal cartilage among Vertebrates is briefly sketched, and 

 its importance in the Mammalia dwelt upon. Though in the majority of 

 Mammals it is absent or rudimentary, in the Platypus it forms the large ro- 

 stral cartilage, while in Echidna it forms the axis of the beak. Among the 

 higher animals it is held to be represented by the cartilage of the papilla in 

 Marsupials , and by an interesting median cartilage in an Australian Bat 

 [Miniopterus sp.). — 2) On a small Fossil Diprotodont Marsupial, with large 

 grooved Premolars. By R. Broom, M.B., CM., B.Sc. A more complete 

 description from more perfect specimens of the little fossil Marsupial de-, 

 scribed under the name Burrawys parvus at the June meeting. — 3) On a 

 small fossil Petaurm-lïkQ Marsupial. By R. Broom, M.B. , CM. B.Sc. 

 Under the provisional name Palaeopetaurus elegans is described a small fossil 

 Marsupial from a bone-breccia deposit in the neighbourhood of Taralga. It 

 is closely allied to Petmirus, but differs in a number of dental details, chiefly 

 the greater proportional development of the upper pm^. — 4) On the Organ 

 of Jacobson in an Australian Bat [Miniopterus). By R. Broom, M.B., CM., 

 B.Sc. A description is given of the Organ of Jacobson in an Australian 

 Bat [Miniopterus] , and its affinities dealt with. Until the recent discovery 

 of a Jacobson's Organ in Vesperuffo, the Chiroptera have been considered 

 devoid of such. In Miniopterus the organ attains a very great development, 

 and presents certain features unlike those of any other form hitherto exa- 

 mined. — 5) Observations on a gravid Echidna. By R. Broom, M.B., 

 CM., B.Sc. From observation on a gravid female the period of gestation 

 is believed to be not more than 26 or 27 days, and certainly not less than 

 18 days. — 6) Ethnological. — 7) Botanical. — 8) Preliminary Note on, 

 the occurrence of a placental connection in the Bandicoot [Perameles ohesula) : 

 and on the Foetal Membranes of Certain Macropids. By Jas. P. Hill, 

 F.L.S. The author in this preliminary note records the discovery of a true 

 allantoic placenta of the discoidal type in Perameles ohesula. The foetal 

 membranes have the same general arrangement as those of Phascolarctus. 

 The allantois consists of a long stalk and a terminal expanded and much 

 flattened vesicular portion. In the stalk the allantoic cavity is reduced to a 

 narrow compressed canal which opens distally into the cavity of the vesicu- 

 lar portion of the allantois. This latter cavity is also greatly compressed, 

 appearing as a long fissure in sections. The mesoderm of the outer surface 

 of the placenta is fused with the mesoderm of the serous membrane , and, 

 not only so, one can no longer make out the ectoderm of the serous mem- 

 brane as a distinct and independent layer. It seems more probable that the 

 ectoderm of the serous membrane has fused with the uterine mucosa than 

 that it has entirely disappeared. As a consequence of the union of foetal 

 and maternal tissues the uterine wall exhibits certain modifications. The 

 columnar epithelium which lines the non-pregnant uterus has disappeared, 

 and a short distance below the surface of the mucosa groups of large cells, 

 probably of the nature of decidual cells , are present. The allantoic vessels 

 consist of a large vein, on either side of which is a smaller artery. They 

 pass down the allantoic stalk, branch out on the inner or coelomic surface 

 of the vesicular part of the allantois, and then extend round into the mesen- 



