172 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Physiological Study of Metamorphosis.* — J. Sosnowski has 

 studied the quantity of carbon dioxide eliminated by the larvae of 

 Musca vomitoria and Lucilia ccesar in the later stages of their develop- 

 ment. The quantity eliminated decreases as the larva approaches the 

 pupa stage. Illumination increases notably the quantity of carbonic 

 acid eliminated, especially towards the transformation into pupae. The 

 quantity of ammonia liberated diminishes regularly from the time the 

 larvae cease to eat until they become pupae, and the quantity is increased 

 by illumination. As for the liberation of carbonic acid from the pupae, 

 it decreases rapidly during the first day, remains almost constant for 

 several days, and increases again to the old amount as the fly prepares to 

 emerge from the cocoon. 



Pseudogyny in Formica, and its Cause.j — E. Wasmann returns 

 with fresh light to a discussion of "pseudogyny" in Formica sanguined, 

 .&c. A pseudogynous form exhibits a somewhat deformed combination 

 of the thorax-structure of a female with the abdominal development 

 and body-size of a worker. It seems to be due to a post-embryonic 

 inhibition of the typical female constitution, probably occurring in 

 larvae which iwere originally destined to be females, but were subse- 

 quently reared as workers. What Wasmann has now shown is, that the 

 •occurrence of pseudogyny is in causal connection with the rearing of 

 larvae of the myrmecophilous beetle Lomechusa strumosa. It is never 

 seen except in species and in colonies of Formica which rear these 

 beetle-larvae or similar larvae, e.g. of Atemeles or Xenodusa. The care 

 of these guest-larvae seems sometimes to bring about an aberration or 

 mistake in the rearing of the ant-larvae. 



Stingless Bees (Melipona) of Para. J — A. Ducke gives an account 

 of the representatives of the genus Melipona found in the state of Para. 

 No fewer than 42 species are described, and Trigona is recognised as a 

 necessary sub-genus. 



New Termites, Termitophils, and Myrmecophils.§ — E. Wasmann 

 reports on a collection chiefly made by Dr. W. Horn in Ceylon. He 

 •describes Arrhinotermes heimi g. et sp. n., Microtermes globicola g. et 

 sp. n., Speculitermes cycloids g. et sp. n., and numerous new species. He 

 gives an account of some new termitophilous Coleoptera, Diptera, 

 Hymenoptera, and Pseudoneuroptera, and of three new myrmecophils. 

 This is the author's 129th contribution to this general subject. 



Guests of the Dorylinae.|| — E. Wasmann has continued his inter- 

 esting investigations on the Coleopterous (Staphylinid) guests of the pre- 

 •daceous driver-ants (Dorylinae), such as Eaton in South America and 

 Anomma in Africa. The guests may be divided into four groups accord- 

 ing to the nature of their adaptation to their hosts. (1) There are 

 guests of g the "Mimicry-Type" e.g. Mimeciton, which in superficial 

 sculpture, form, antennae, and coloration resemble their hosts ; they 



* Bull. Acad. Internat. Sci. Cracovie, 1902, No. 8, pp. 5G8-73 (3 curves). 



+ Verl.. Deutsch. Zool. Gos., xii. Vers. (1902) pp. 98-108 (1 pi.). 



% Zoul. Jahrb., xvii. (1902) pp. 285-328 (1 pi ). 



$ 'I om. i-it., pp. 99-164 (2 pis.). 



Jl Verh. Deutsch. Zool. Ges., xii. Vers. (1902) pp. 86-98 (1 pi.). 



