xviii Transactions of the South African Philosophical Society. 



driest places, with an annual average of 2J- inches, Pella being close 

 up with 3J. 



A lengthy discussion of the harmonic elicits some interesting 

 conclusions with regard to the laws obeyed by the rainfall of the 

 country. It seems to follow from this that the rainfall of Natal 

 is more nearly related to that of the country lying between Cape 

 Agulhas and Mossel Bay than it is to that of the Port Elizabeth 

 area. 



Eain on the central tableland comes chiefly with a N.E. wind and 

 a falling barometer ; on the coast of Natal with a S.W. wind and 

 a rising barometer. In this and other respects there is scarcely 

 any special agreement between the rain conditions of the two 

 areas. 



The cloud statistics of a number of places are discussed as far as 

 the quality of the results justifies. There seems not to be so close 

 a connection between cloud and rainfall as might have been 

 expected. 



The author's final conclusion is that the rain of Central South 

 Africa originates in the main in the doldrums, being reinforced more 

 or less by the moisture evaporated from the Indian Ocean ; and 

 that the aridity of the west coast is not caused, as Buchan asserts, 

 by the southern anticyclone belt, but simply by the coldness of the 

 water. 



Dr. E. Broom gave an account of the evolution of the mammalian 

 shoulder girdle in the light of recent researches in South African 

 palaeontology. 



The Labyrinthodont type of girdle, which may be taken as 

 ancestral to all the later types, was shown to consist of the three 

 cartilaginous elements — scapula, coracoid, and precoracoid, but of 

 which only the scapula is usually ossified, with, in addition, five 

 membrane bones — a median interclavicle, two large flat clavicles, 

 and two slender supraclavicles or cleithra. 



In Pareiasaurus and in Dicynodon the same 11 elements are still 

 found, and all ossified. The scapula is well developed, and has 

 a distinct acromion process. 



In the Theriodonts the cleithrum appears to be lost. 



The Monotreme shoulder girdle differs from that of the Dicyno- 

 donts in the loss of the cleithrum and in the reduction of the 

 precoracoid. 



In the festal Marsupial there is still a well-developed coracoid 

 which articulates with the sternum, and the precoracoid is possibly 

 represented by the coraco-clavicular ligament* At an early, stage 



