16S FETCH : 



to the Hypocreacese, while Aschersonia is pj'cnidial and belongs 

 to the Nectrioidacese. It was originally supposed that the 

 species of these genera were parasitic on the plants on which 

 they occurred, but about twenty years ago it was discovered 

 that certain species of Aschersonia were not parasitic on the 

 plants, but on insects infesting the plants. Further investi- 

 gations have shown that this is true, not only of all species of 

 Aschersonia, but also of all species of Hypocrella, a genus 

 whose members bear a striking resemblance to those of 

 Aschersonia. Moreover, the opinion has become general 

 that Aschersonia is merely the pycnidial stage of Hypocrella, 

 and the accumulated evidence on this point is now so strong 

 that the correctness of this view cannot be doubted. 



These entomogenous fungi are parasitic, as far as has been 

 determined, only on insects belonging to the Lecaniidse and 

 the Aleyrodidse. The species exhibit at least one point of 

 difference which is correlated with the division of insects on 

 which they are parasitic, and they may accordingly be con- 

 veniently divided into two groups, the Lecaniicolse and the 

 Aleyrodiicolas respectively. 



The foundation of the present account of these genera was 

 based on a collection of entomogenous fungi which had been 

 amassed by ]\Ir. E. E. Gieen, formerlj'- Grovernment Ento- 

 mologist of Ceylon, and the well-known authority on Coccidee. 

 It has since been extended bj'' the examination of numerous 

 gatherings made in Ceylon during the last fifteen j-ears ; of 

 the tj'pe specimens in the principal European Herbaria ; and 

 of collections which have been generously lent by mycologists 

 in the tropics and by speciahsts who have contributed to the 

 investigation of the tropical fungus flora. My thanks are due 

 to the Directors and officers in charge of the herbaria of the 

 Royal Botanic Gardens, Kew ; the British Museum (Natural 

 History) ; Berhn ; and Paris, for the opportunities afforded 

 me of examining the species of these genera in those collections ; 

 to Professors von Hohnel, Ito, Moller, Patouillard, Penzig, 

 Raciborski, Saccardo, Spegazzini, H. Sj'dow, Theissen, and 

 A. Zimmermann for the loan of types ; and to Dr. E. J. 

 Butler, Mr. F. W. South, Mr. H. S. Fawcett, and Dr. E. D. 

 Merrill for general material. Professor Thaxter has liberally 



