4 86 



FAMILY SCOLYTIDAE 



it on the bark of the tree. It apparently hides until it can safely enter a 

 tunnel already extending down to the bast layer. 



This insect is of such importance that the remainder of its life history 

 urgently requires working out. We require to know whether the number of 

 generations it passes through coincide with those of the Sphaerotrypes, and 

 the exact number of them. The larval and pupal stages and beetle stages 

 of the first generation of the year, March to May, would appear to coincide 

 with those of the insect it preys upon, and it is not unlikely that the 

 remaining life cycles of the year will be found to do so. 



Tillioera assamensis, Stebbing, sp. nov. (p. 187). The beetle feeds on the 

 mature forms of the Sphaerotrypes and also of Platypus 

 cnrtus (p. 624), and on species of Diapus (p. 630). 



Beetle. Squarish, with an ant-like vertical head and " shoul- 

 ders " to the elytra, which give it some superficial resemblance to a 

 longicorn beetle. Black, with transverse white bands on the elytra. 

 Antennae knobbed. Head black, shining, a few scattered black 

 bristles on vertex, the front being set with close long white hairs. 

 Eyes black, prominent. Thorax red, shining, with a deep trans- 

 verse depression across the middle, and a marked channel just 

 above the basal margin. Clothed with scattered stiff long black 

 bristles, a bunch of white ones projecting from the lateral margins 

 just above the base. Elytra black, set with rough scales. A band 

 of white pubescence, under which the elytra are yellowish red, starts 

 from the base on either side of the median suture and is produced 

 upwards for about a third, when it expands laterally to the outer 

 edges in the form of a broad transverse white band whose apical 

 margin is produced medianly into a sharp point reaching to the 

 upper third of the elytra. A second narrower white transverse band 



traverses the elytra just above the apices, which are black, clothed with more sparsely set 

 white hairs. Under-surface black, the thoracic segments clothed with long thick spiny white 

 hairs, most numerous laterally. Upper portions of femora yellow, rest of leg black, clothed 

 with long yellow and white hairs Antennae yellow. Length, 6.5 mm. 



The smaller size and position of the white bands on elytra easily distinguish this insect 

 from Tluinasiinus liiialaycn*is. 



Life History. This insect was first taken on the wing whilst I was pro- 

 ceeding through the Hultugaon forests on an elephant. It was subsequently 

 caught flying round and running about on the bark of newly felled sal-trees in 

 the Kachugaon (Polo and Hel blocks) forests. It is an extremely active insect, 

 resembling a Cicindela in its movements, as it flies an d runs with great rapidity. 

 Beetles were kept for some days and fed with living Sphaerotrypes, Platypus, 

 and Diapus beetles. They were found to consume a considerable number of 

 the bark and wood beetles per day, taking about fifteen minutes to eat one 

 Sphaerotrype beetle. Their habits, method of feeding, etc., are similar to those 

 described for T. himalayensis (p. 509). There is still a considerable amount 

 of information required about this very useful insect. We need to find its 

 grubs, which almost certainly feed upon the bark- and wood- boring scolytid 



FIG. 319. 



Tillitvra assamensis, 



Steb., predaceous upon 



Sphaerotrypes asta- 



mensis. Goalpara, 



Assam. 



