160 



larger size, and in the female by no sign of shining black frontal 

 triangle. T. tropicus from Japan almost always has rather a broad 

 (not very contracted from tip to bottom) frontal stripe which bears 

 generally two quite separated frontal calli and is of medium size. In 

 fact, one may sometimes say, that our form belongs to the intermediate 

 one between tropicus and niontanus from Europe, but I do not hesitate 

 to determine it as a form of the former. 



A female type under the name Tabanus sakhalinensis in 

 Matsumura's collection from Todoroki, Sakhalin Island, is quite identi- 

 cal with some of the British forms of tropicus and is not a distinct 

 species. 



These flies occur only in the northern part of Japan, Hokkaido 

 (Honshu) and Sakhalin Islands, and in the latter Island it is rather 

 common, while in the former it is probably not very abundant. I 

 noticed that it attacks the belly of horses or cattle in Hokkaido, but 

 I have no other records from an economic point of view. I have 

 records from Kioto, Tokio, Rikubetsu, Josankei, Sapporo, Galkino, 

 Shisuka, Solowiyofka, Shimiz'i Ushoro, and Galkinowraske, from June 

 20th to August 8th. 



4. Therioplectes distingaenduSf Verrall. (PI. III. figs. 6 & 7. 



(!<ubnr.:-Ahu). 

 Brit. Flies, V, p. 371, fig. 230, 1909. 



Tabanus tropicus Matsumura, Thous. Ins. Japan, II, p. 73, pi. XXII, 

 fig. 6, 1905. 



A rather large species with the abdomen very extensively bright 

 brownish orange except for the narrow black dorsal stripe and tip ; 

 closely allied to the preceding species. 



Female. Head very slightly longer than or about as long as 

 the thorax, about one-third as long as its width, slightly arched. 

 Frontal stripe slightly narrowed, below to the front eye-angles, and 

 nearly four times as long as its widest part or about five and a half 



