ORTHOPTERA. 161 



(DRTHOPTERA. 



Note on the Geographical Distribution of the Eumastacidae. 



By MALCOLM BUEE, F.Z.S., F.E.S. 



Having recently had occasion to study in some detail the insects of 

 this family, I have been much struck with their geographical distri- 

 bution, and a few notes on this point may be of interest. 



The Eumastacidae are a family of the Acridiodea, well marked, it is 

 true, but showing affinities with the Proscopidac and Pneiimnridai', 

 both exceedingly restricted in distribution, and presenting certain 

 analogies with the Tettif/idae. They are all very peculiar in form, and 

 afford some very striking examples of mimicry and adaptation to their 

 surroundings. About a hundred species are known to science, but 

 none are very common ; new species are continually coming to hand, 

 in fact, about two years ago scarcely more than thirty species had 

 been described ; they do not appear to be common anywhere, and are 

 rare in collections. With a few exceptions they are confined to the 

 tropics. Koughly speaking, from a geographical point of view, they 

 fall into three groups, the Oriental, the Ethiopian, and Neotropical. 

 We will now consider them more in detail. 



The first group, Chorocti/pi, contains several genera in which the 

 pronotuni is greatly compressed and elevated, recalling certain I'ctti- 

 tjidae and Meinbyacidae. They were at first considered to be essentially 

 Oriental, but recent discoveries have brought to light a number of 

 African forms. The genus Choroeti/pus, Serv., is found in India, 

 Borneo, and Java. Plujllochoyeia appears to be confined to the Mala- 

 bar coast and to Ceylon. Scirtntiipm, Br., is more widely spread ; 

 three species are known, occurring respectively in Borneo, west Africa, 

 and Ceylon. The two species of <>rcJiet;/piis are confined to Ceylon. 

 The genus Flat/iotrijitas:, which is close to CIton)eti/pi(s, is exclusively 

 African, but one small species is found in Sokotra, which appears to 

 be a stepping stone to the Oriental region ; an intermediate monotypic 

 genus, Phaidotijptis i/yanti, Burr, seems to be peculiar to that island. 

 Thus it will be seen that, with a (ew exceptions, the Choroeti/pi are an 

 Oriental group. 



The next group, the Kriantld, are also Oriental, but their distribu- 

 tion just reaches the confines of the Australian region. Erianthua is 

 widely spread throughout the Oriental region, EupatrUh's in Borneo, 

 In'nnia in south China, Avhile Adrapetes is found in NeAV Guinea. This, 

 therefore, is also an Oriental group. 



The (jOiiijjJioiiiastaces comprise one anomalous genus ; four species 

 are known, of which two occur in the Punjab and in Kashmir, while 

 two others are found in central Asia, within the usually accepted 

 limits of the Palasarctic region. In their form as well as in their dis- 

 tribution, they are exceptional among the I'^onaatacidae. 



The Enicii again are essentially Oriental ; ' Enuius contains several 

 species found in Sumatra, Borneo, the Philipines, and Java ; Mjiesidci 

 has the same distribution, and Mafitacidcs consists of two small 

 apterous forms, occurring in southern India. China is a monotypic 

 form occurring in southern China. 



The above mentioned groups, then, may be regarded as charac- 

 teristic of the Oriental region, although certain forms slightly overstep 

 the limits. 



