! 



farther north. No more wore noticed till September 2nfl, 1010, when a 

 t'enialo occurred at Southwold ; but on September 7th, 1911, the species 

 was again common, this time entirely upon marram grass at Easton Broad 

 with six-sevenths of the individuals of the male sex. I last saw a single d on 

 reeds, yet another mile further north and still on the coast in Covehithe 

 Broad, on September 10th, 1912 ; and none have subsequently occurred, 

 though annually looked for, since that time. That the eruption of 

 shingle at Buss Creek should synchronise with the species' first appears 

 ance may be accidental, but is remarkable ; and it appears obvious that 

 there was a steady tendency to northern expansion, possibly checked 

 southward by the presence of the town : in its actual direction are 

 nothing but intervening bluffs crowded with heaths. The first step in 

 the problem's elucidation would be the discovery of this parasite's host ; 

 and this I can suggest. The smaller Campoplegid genera, whereof 

 Aiigitia is one, are near!}' confined in their parasitism to the smaller 

 Sawflies and Microlepidoptera ; of the latter nothing unusual occurred 

 here, of the former the three most probable species were PachynemaUts 

 Jlaviventris Htg., P. irisignatiis Fst., ?i,x\^ Pteronus mirtisfinis Thorns. 

 The two former have always occurred on the Arundines and Psammae 

 here, so may perhaps be neglected ; but the last here turned ujj for the 

 first time on September 4th, 1907. I feel confident that one of the 

 three was the host of this new British Ichneumon, none of my fifty 

 specimens of which has the scape at all pale. 



Moiik,s' Si-fham House. 



Auoemher 20th, 19:20. 



ON NABIS LATIVENTRIS Boh. (HEMIPTERA-HETEROPTEEA). 

 BY E. A. BUTLER, B.A., B.SC, F.E.S. 



There are man}^ points in the natural history of this Hemipteron 

 which are of great interest, and some also that still need elucidation. 

 The object of this paper is to detail what is already known, and ta 

 indicate something of the problems that are still unsolved, in the hope 

 that Hemipterists may take such opportunities as come in their way of 

 studying the species, and so of completing our knowledge of its 

 bionomics. 



The adult 5 . like those of the rest of the genus, is furnished with 

 an ovipositor which consists in the main of four saw-like parts sliding 

 upon one another, something like those of saw-flies ; each " saw " is 

 strongly serrate at the apex for a distance of about | mm., and the 



