( 1^.7 ) 



V. The Terminal Abdominal Siruciures of the Primitive 

 Australian Termile, Mastotermes darwinensis Froggatt. 

 By G. C. Crampton, Ph.D., F.E.S. (Massachusetts 

 Agricultural College, Amherst, Mass.). 



[Road February 4th, 1020.] 



Plate IV. 



Through the kindness of Dr. R. J. Tillyard I have been 

 able to examine a few specimens of the extremely interesting 

 Australian termite, Mastotermes darwinensis Froggatt, 

 preserved in spirit. Since these insects are in some respects 

 among the most primitive representatives of the order 

 Isoptera, and since they are available for study to but few 

 fortunate individuals, it may possibly be of some interest 

 to describe briefly their terminal abdominal structures, 

 which have not been figured before, so far as I am aware. 

 The terminology here ajiplied to the parts is that proposed 

 for insects in general in a paper dealing with the terminal 

 structures of male insects, published in the June 1918 issue 

 of vol. xiii of the Bulletin of the Brooklyn Entomological 

 Society (pp. 49-68), and in an article deahng with the 

 terminal structures of female insects, published in the 

 December 1917 issue of vol. xxv of the Journal of the New 

 York Entomological Society (pp. 225-237). 



There were two types of winged specimens in the material 

 which I examined; but since I was permitted to retain 

 only one winged specimen (which I wished to keep intact 

 for a further study of the external morphology of these in- 

 sects, and for a comparison with other termites) I have been 

 unable definitely to determine, by dissecting them, which 

 of the winged foriTis are males, and which are females. In 

 the alate forms of many termites, however, the males bear 

 styli and the females do not, and from what is known of 

 related forms, I think that we are justified in assuming 

 that in the wdnged caste of Mastotermes also, those forms 

 wdiicli bear styli are males, and those which do not are 

 females ; but until this point has been definitely determined 

 by dissection, the interpretation here given must be regarded 

 as purely provisional. I might state, however, in this 



TRANS. ENT, SOC. LOND, 1920. — PARTS T, II. (JULV) 



