1922.] 39 



approximately equal j. They were as numerous as this over an area of about 

 60 square feet of the ceiliug, and beyond that became less and less so as one 

 got further away from that corner, but nowhere failed entirely, and it would 

 be safe to estimate that there were about 50,000 present. Dr. Sharp, in the 

 Camb. Nat. Hist., Insects, pt. ii, p. 506, speaks of " many millions " occurring in 

 a single apartment ; had there been one million in my room there must have 

 been at least a dozen per square inch over the whole of the ceiling, and many 

 millions would mean several layers thick : do they really occur in this 

 abundance ? I could see no explanation of their presence ; the house is quite 

 surrounded by garden ; not far away is a place where under trees the grass is 

 allowed to grow rough and is only scythed occasionally, not mown at all, but 

 otherwise I see no ground where the species would be likely to breed in special 

 numbers. They certainly did seem to come in after the first cold nights at the 

 end of the summer (there ha,d been one or two slight ground-frosts imme- 

 diately before their arrival) ; but if they come into the house for the purpose 

 of hibernation, a suggestion to which Dr. Imms refers, then the question 

 immediately arises : How is it that they died so soon ? For after about two 

 weeks they began to drop, and before long were all dead ; not one has 

 survived. Moreover, why did they come into the rooms on the second floor 

 only and none into those immediately beneath ? In the latter rooms we had a 

 similar visitation, on a much smaller scale, of another insect altogether — 

 a Chalcid, which Mr. G. T. Lyle has kindly identified for me as Fteyumulus 

 deplanutus Nees, which is also known to have this habit of entering houses. 

 Can there be any connection between the two species by any chance ? 

 I only came to live in this house in October 1920, so yet have to learn 

 whether either or both of these insects will prove to be annual visitors, or 

 if the unusual character of the summer of 1921 may be partly responsible. — 

 CoLBRAN J. Wainwright, Daylesford, Ilandsworth Wood, Birmingham : 

 January 1922. 



"Mecoptera: Monographic Revision." By P. Esben-Petkrsen, 

 " Catalogue Systeniatique et Descriptif des Collections Zoologiques du Baron 

 Edm. de Selys Lungchamps." Fasc. v (deuxieme partie). Pp. 1-172, 

 pis. i and ii, fig^. 1-188. Brussels, 1921. 



Another addition has just been made to the series of magniticent mono- 

 graphs forming the Selysian Catalogue. On the present occasion the 

 particular group of insects dealt with is that known as the Mecoptera, or 

 Scorpion-flies, of which 179 recent species, belonging to 17 genera, have been 

 described. These are arranged in five families, the largest of which, the 

 Panorpidae, is subdivided into three subfamilies. That family, with 8 genera 

 and 112 species, is represented in Europe, Asia, Australia, New Zealand, and 

 North America. The Meropidao (containing only Merope tuber Newman) and 

 the Notiothaumidae (consisting of Notiothamna reedi McLachlan) occur in 

 the United States and Chile respectively. The family Boreidae comprises the 

 single genus Boreus, with 10 European and North American species. Finallj'', 

 the Bittacidae include 6 genera and 55 species, from Europe, Asia, Australia, 

 Africa, and North and South America. 



