102 '^'^y- 



Bagous angustatus Thorns., Opusc. ent. ii, 1870, p. 1-39. — Pro- 

 hagons convexicoUis Sharp, Ent. Mo. Mag., lii, p. 225. (nee B. con- 

 vexicollis Boh.). 



This is a very variable species. It is of more elongate form than 

 any of the Bayous proper, and has a longer abdomen, with a longer 

 and narrower intercoxal process, and the third and fourth segments 

 not so short. Usually it is more or less tessellate, the colours being 

 white and obscure black ; biit the coloration varies greatly, and in 

 some cases the insect looks almost white. 



The aedeagus is very much simpler in structui-e than it is in 

 Bagous ; there is no transverse bridge at the base of the upper lip ; 

 the basal callipers are minute, and the superior processes of the tegmen 

 are long but extremely slender, and basally conjoined ; the tip of the 

 median lobe is blunt and not pointed. 



The largest specimens have occurred in Sheppey. A specimen of 

 the white form from Finchley is in the Crotch collection, bearing 

 Brisout's label, " tempestivus.^^ 



B. dilatatns is stated in the European catalogue to be a synonym 

 of " tempestiviisy Accepting that as correct, I must at present place 

 angustatus Thomson as a variety, although it is given a separate place in 

 the European catalogue. At first I thought it probably another species, 

 but on renewed examination I am not able to find any satisfactory dis- 

 tinctive characters in the external structure, and so far as I can judge 

 from the examination of old, dried specimens, the aedeagus is very 

 similar in the two forms, being only a little more parallel in angustatus, 

 with the tip slightly more rounded. At present it is better to treat 

 the two as one species. 



B. angustatus used to occur in the Hammersmith marshes in 

 company with Lypriis cylindrus ; I have not seen any example from 

 elsewhere that I can with certainty refer to it, though Mr. Bedwell 

 has found, at Askham Bog, Yorks., two specimens that are scarcely 

 different. At Hammersmith the form occurred with cnemerythrus ; 

 and at Kye, Bedwell has found a specimen very near, if not it, in 

 company with cnemerythrus. 



As regards the name of the species, Boheman, in Vol. iii of 

 Schonherr's work, recorded " tempestlvus " as British, on the authority 

 of a specimen sent to him by Spence. In Vol. viii, p. 83, he revised 

 his work on Bagous, and states expressly that English and French 

 " tempestivus " were not that species, and he describes them as 



