562 MAJOR, E. E. AUSTEN ON THE 



In addition to sexual dimorphism of the kind just referred to, 

 difficulties of determination in this genus are increased by the 

 fact that in the case of certain species (at any rate P. tabanimis 

 Thunb. and P.pictus Wied. — see below) the female abdomen, at 

 least in dried specimens, sometimes shows colour-dimorphism as 

 well. Failure to realize the occurrence of this phenomenon led 

 Enderlein into error in constructing his synoptic tables (Zool. 

 Anz. xli. pp. 101, 107 (1912)) — a fact which has already been 

 pointed out by Hermann (Deutsche Ent. Zeitschr., Jahrg, 1916, 

 p. 48 (1916)). 



The number of species of Pantophthalmus recognized as valid 

 in Kerbesz's ' Catalogus ' (vol. iii. 1908) is fourteen. This total 

 does not include Acanthomera teretruncum Fiebrig ( = Pantoph- 

 thalmus pictiis {Acantho7nera picta) Wied.), since the description 

 of the latter (1906) appeared between the compilation and 

 publication of tho volume of the late Dr. Kert6sz's monumental 

 work in which the Pantophthalmidoe are included. Between 

 1908 and the present time, descriptions of nine species of Pant- 

 ophthalmus supposed to be new have been published, includ- 

 ing seven by Enderlein and one each by Hermann and Knab ; 

 while Enderlein has rightly sunk Fiebrig's designation Acantho- 

 mera teretruncum as a synonym, besides disposing of P. helleri 

 Enderl. in a similar manner. Thus for the moment the number 

 of species of Pantophthalmus assumed to be valid stands at 

 twenty-two. In the following pages, however, the names of no 

 fewer than nine of these are shown to be synonyms, while six 

 species are described as new ; so that, as the result of the 

 present paper, the genus Pantophthalmus is to be regarded as 

 consisting of nineteen recognized species. 



The genotype is Pantophthalmus tabanimis Thunb. 



Pantophthalmus tabaninus Thunb. 



Pantophthalmus tabaninus Thunberg, loc. cit. p. vii (1819), 



Acanthomera seticornis Wiedemann, Auss. zweill, Ins. i. 

 p. 108, Taf. ii. figs. l-«-l c (1828). [New synonym,] 



Acanthomera heydenii Wiedemann, oj). cit. p. 555 (1828). 

 [New synonym.] 



Acanthomera immanis Wiedemann, op. cit. ii. p. 623 (1830), 

 [New synonym,] 



Acanthomera rubriventris Bigot, Ann. Soc, Ent. France, 5*^ Ser., 

 T. X., Bull. p. V (1880). [New synonym.] 



Pantophthalmus Jasluosas Knab, Insec. Inscit. Mens. vol. ii, 

 no, 2, p. 27 (February 1914). [New synonym.] 



According to Thunberg (loc. cit.), the type of P. tabaninus was 

 obtained in St. Barth61emy I., in the- West Indies. 



Among the synonyms recorded above, the name Acanthomera 

 seticornis (like Pantophthalmus tabaninus itself) was originally 

 applied to the c? insect, while the designations Acanthomera 

 heydenii, A. immanis, and A. rubriventris were bestowed upon 



