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region were exhibited together with, serial photographs of the younger Orni- 

 thorhynchus. The following features are revealed and illustrated by the 

 models: — 1) The complete continuity of the nasal floor cartilage and the 

 extensive marginal cartilage of the upper lip, which in the adult are sepa- 

 rated by the prem axillae. 2) As a result of this continuity the premaxillae 

 arise each as two entirely distinct bony splints on the dorsal and ventral 

 surfaces of the cartilaginous plate aforesaid. 3) The great forward expansion 

 of the so-called rostral cartilage of the Ornithorhynchus is seen to be due to 

 the forward growth of two bilateral alar expansions of the same cartilage, 

 which tend to meet in front, after enclosing a deep notch corresponding to 

 the hiatus described by Broom in the rostral cartilage of the adult. 4) The 

 ventral lamellae of the premaxillae are provided with true palatine processes 

 directed backwards paramesially. In the older of the two stages of Ornitho- 

 rhynchus there exists, quite independently of the palatine process, and sepa- 

 rated from it by a considerable interval, a separate ossification for the 

 dump-bell-shaped bone, which is thus proved to be a perfectly distinct ele- 

 ment — a true anterior vomer. 5) Anteriorly , the ventral premaxillary 

 splints turn up dorsally in front of the anterior extremity of the snout in 

 both Ornithorhynchus specimens, in the form of rather attenuated trabeculee, 

 lodged in the notch between the alar expansions of the rostral cartilage. 

 Above this plane they fuse and are continued dorsally into a remarkable 

 osseous mass which forms a definite skeletal foundation for the caruncle, 

 and may therefore be named the os carunculae. This is at its maximum 

 development in the younger stage of Ornithorhynchus, and is undergoing 

 resorption in the older; whilst in the Echidna model it is only represented 

 by a small nodule of bone which has lost all connection with the premaxillae. 

 From Seydel's figures of earlier stages it is evident that the Echidna condi- 

 tion is originally identical with that of Omithorhynchux, though it would 

 appear to exist in a less exaggerated form. 6) The cartilaginous septum of 

 both Monotremes exhibits an oval "internasal fenestra" immediately behind 

 its anterior termination at the prerostral notch. A similar fenestra, accor- 

 ding to W. K. Parker, is "a common feature in low Eutheria." — Mr. Percy 

 Williams showed a beautiful specimen of the rare butterfly, Heteronympha 

 paradelpha, Lower, from Berrima, N.S.W. ; and he contributed a Note in 

 reference to its capture. — Mr. A. J. Campbell, of Melbourne, exhibited 

 a number of lantern slides illustrative of Australian birds, their nests and 

 eggs, photographed under natural conditions. — Mr. Palmer contributed a 

 note describing his experiences after being bitten by a black snake in 

 February last. He also exhibited a snake which hed attacked a member of 

 his family; and a number of insects from Lawson. — Mr. Fletcher exhi- 

 bited several specimens of a small freshwater crab which Mr. Whitelegge 

 had kindly examined, and identified as Hymenosoma lacustris, Chilton. The 

 species was originally described from New Zealand, but was subsequently 

 obtained in Lord Howe Island by Mr. Whitelegge, who was a member of 

 the Australian Museum party which visited the Island in 1887. The speci- 

 mens exhibited were forwarded by Mr. E. Stuart Dove, who collected them 

 in the north of Tasmania. 



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