AUGUST 19, 1921 proceedings: philosophical society 347 



the islands. About 70 per cent of the species listed are supposedly endemic 

 This number of endemic forms is an unusually high percentage for an island 

 favma and indicates a very long isolation. 



In a preUminary discussion of the zoogeographical position of the islands 

 it is shown that the ant fauna is not related to that of any one region but 

 consists chiefly of types that formerly were of wide distribution and thus 

 supports the idea that Melanesia has served, as far as the land fauna is con- 

 cerned, as a biological conservatory. Fiji is the eastern limit of this region 

 and has been isolated longer that the islands further west. W. M. M. 



ENTOMOLOGY. — Diptera of the superfamily Tipuloidea found in the Dis- 

 trict of Columbia. C. P. Alexander and W. L. McAtee. Proc. U. S. 

 Nat. Mus. 58: 385-435, pi. 26. 



This paper forms another one of the series of insect papers which endeavors 

 to make it possible for local workers to become acquainted with the fauna 

 of the District of Columbia and vicinity. The insects belonging to the 

 superfamily Tipuloidea were commonly called crane-flies, and this paper 

 tabulates all the species known to occur locally, gives notes on the habits 

 of the adults and larvae, and distribution and dates of flight of the various 

 species. The introduction briefly summarizes the history of this science as 

 far as pertains to this region and the paper is followed by a bibliography of 

 titles. One plate illustrates the venation, 40 genera are included. Of the 

 species listed 87 are described from material which was collected in this region, 

 chiefly by the activities of the late C. R. Osten Sacken. S. A. Rohwer. 



ENTOMOLOGY. — A revision of the North American species of Ichneumon- 

 flies belonging to the genus Apanteles. C. F. W. Muesbeck. Proc. U. 

 S. Nat. Mus. 58: 483-576. 1921. 

 The Ichneumon-flies of the genus Apanteles are small, usually black, 

 insects which in the larval stage are parasitic on the larvae of lepidopterous 

 insects. The above-mentioned paper is a revision of the species of North 

 America, including the West Indies. The revision is based largely upon 

 the extensive collections of the National Museum and 164 species are recog- 

 nized. The types of most of the species have been studied by the author and 

 besides pointing out some synonymy he has described 36 new species. The 

 descriptive part of the paper is preceded by a synoptic key and followed by 

 an aphabetical list of hosts, and a species index. S. A. Rohwer. 



PROCEEDINGS OF THE ACADEMY AND AFFILIATED 



SOCIETIES 

 PHILOSOPHICAL SOCIETY 



849th meeting 

 The 849th meeting of the Philosophical Society of Washington was held in 

 the Assembly Hall of the Cosmos Club on March 26, 1921. It was called to 

 order by President Faris, with 65 persons present. The program was as 

 follows : 



O. S. Adams: Authalic latitude, a cartographic expedient. (Illustrated.) 

 It has been found by many scientific investigations of various kinds that 

 the shape of the earth, as a whole, is very nearly that of an ellipsoid of revo- 

 lution with the equatorial diameter about 26 miles longer than the polar 

 diameter, the axis of rotation of the generating ellipse. It is evident that 



