( Ixxi ) 



- April 22, I'.tls. 



" I think the following may interest you, as 1 believe 1 

 told you 1 was taking exception to Geoffrey Smith and 

 Hamm's conclusions (in the Quart. Jinan. Microscop. Sci., 

 vol. 60, Pt. 3, Sept. 191 1. p. 135) as to the impossibility of 

 fertilisation of v ; Stylops and the uselessness of the 6* <$ ! In 

 the continuation of my papers on Stylops in E. M. Mag. (1918, 

 pp. 67 and 73) I have given strong arguments of a theoretical 

 character against these conclusions, but this morning at 

 8.30 a.m. 1 bred a .j Stylops aterrima, Newport, and soon 

 afterwards obtained an evident pairing between it and a $. 

 It is curious that I should have succeeded at the first attempt. 

 I was astonished at the extraordinarily rapid manner in 

 which coupling was effected. Twice the o Stylops was brushed 

 off by the bee {Andrena trimmerana, Kirb.) before it properly 

 mounted it, but the third time it got fairly on and in a second 

 or two was coupled with the minute projecting part of the $. 

 1 had to carry it to another room and find a cyanide bottle 

 to kill it, so that it remained coupled in life for probably 

 1-2 minutes, and in addition it took say 30 sec. to 1 min. 

 to kill the bee. In spite of this, it still remains attached to 

 the $ in the manner shown in the sketch, reproduced in 

 Plate A. 



" ob. pi. is the (generally reddish) oblong abdominal apical 

 ventral plate of the J, from which the aedeagus may be seen 

 entering the 'brood opening' b. op. of the y cephalothorax 

 (/. e. really an opening between head and thorax). 



'" m. is the rudiment of the mandible of the y puparium 

 (for of course what one sees is not really the actual y but 

 the puparium in which it lies). 



" up. in. is the apical margin of the bee's 1th segment, from 

 beneath which the cephalothorax projects. 



"The cephalothorax of the Stylops is seen from the side. 

 so that only one of the mandibular rudiments is visible. 



" The drawing was made in lateral aspect by camera lucida 

 many hours after death, so that contraction of the long 

 slender ; body had taken place. 



"If the J Stylops doc- not become detached in the great 



