378 Mr. A. F. Coventry on the Application of 



the wing, its stem about one-third the length of the cell ; 

 stem of the second about half the length of the cell ; posterior 

 cross-vein nearly its own length distant from the mid ; scales 

 of typical Gulex form. 



Length. — 5 to 5*5 mm. 



$ . — Similar to female, but the abdominal banding very 

 pronounced. Palpi acuminate, black at the apices, paler 

 basally, hairs dark; antennas with flaxen brown plume-hairs, 

 paler at their apices. Fork- scales dense, dark behind as well 

 as at the sides. Fore and mid ungues unequal, the larger 

 with a large tooth, the smaller with a small one, hind equal 

 and simple. Genitalia with a large broad foliate plate. 



Length. — 5 to G mm. 



Habitat. — Obuasi (Dr. Graham). 



Time of capture.— 8. i. 08 ; 10. xii. 07 ; 20. vi. 07 ; 17. 

 vii. 07 ; 7. viii. 07; 20. ix. 07 ; 18, 19. x. 07 ; 13. xi. 07. 



Observations. — Caught on bush-paths. Described from a 

 series of several males and females. It is very marked on 

 account of the pronounced pale scaled thorax. The females 

 show some variation in regard to abdominal banding, some 

 showing it much more prominently than others. 



LIV. — The Application of Mr. G. W. Smith's Theory of 

 Dwarf Males to Myzostoma. By A. F. Coventry, Mag- 

 dalen College, Oxford. 



Mr. G. W. Smith has recently put forward a new theory 

 to explain the complemental dwarf males found among the 

 Cirripedia pedunculata. 



He looks for the interpretation of the peculiar sexual 

 relations among these, and, as he believes, also in the Rhizo- 

 cephala, to the fundamental nature of secondary hermaphro- 

 ditism — i.e., imposed on a primitive dicecism, which we must 

 suppose to have been the original condition among the 

 Cirripedia. 



Smith has found, both by observation and experiment, that 

 this hermaphroditism can only be imposed on males. 



Hence the ordinary monoecious Cirripedes are really males, 

 all the females having been suppressed in the course of 

 evolution ; and the complemental males are in an arrested 

 state of development due to the condition of protandric 

 hermaphroditism — i. e., male generative products ripening 

 before female — through which they at one time passed. 



The same reasoning applies with very little modification to 

 the Rhizocephala. 



