381 



black bristly hairs. This is probably an extremely perfect and rather 

 young fly. The male specimens in my collection may be divided into 

 two groups, of which the first one is rather redder and consists of the 

 species which has a rather large space of the eyes occupied by the 

 large facets, while the other contains the darker species which has a 

 comparatively small area of large facets of eyes ; the female specimens 

 are also divided into two, the species belonging to the first group 

 redder, and other blackish. It is, however, doubtful that this species 

 may be separated into two distinct ones, with only our present 

 knowledge. 



7. exoticus is not uncommon but rather familiar to our students, 

 and I have records from Taihoku, Shinten, Toy en, Hoppo, Karapai, 

 Hokuzanko, Horisha, Giochi, Takao, Kosempo, Arikan, Koshun, Fuho- 

 sho, Kankau, Sokutsu, Kusukusu, and Choshu ; I have no records 

 from other countries. The dates extend from May 2Oth to August 

 2Oth, and it is curious that one of the eariest dates (May 2Oth) is 

 from Taihoku, while the latest (August 2Oth) is from Koshun. 



The females are almost found on the back or belly of Formosan 

 cattle or sometimes buffaloes, free in pastures near villages or towns, 

 from midday to just before sunset, from May to August, and they can 

 sometimes be seen on a country road through wood or bushes, or near 

 a stream ; the males are caught by many collectors on a path between 

 bushes, or in wood or bush, early in the morning or late in the 

 evening; once I took a young male fly on a rock near a river-beach,: 

 about 9 o'clock in the morning, near Horisha. The bite of the 

 females, although not painful, is very severe and draws blood more 

 often than that of any other Formosan horse-fly. 



T. exoticus has a resemblance to Tabanns trigonns, but is easily 

 distinguished from it by its narrower body, by its quite interrupted 

 median triangles of the brownish abdomen, by its darker legs, and by 

 other minor points as described above. Formerly, I have ill-determined. 



