( xlv ) 



" Our only Anthidium, is well known often to select the 

 boring of some Longicorn beetle for its cells, but I have seen 

 it burrow in the decayed beam in a greenhouse and in great 

 plenty in the soft (from age) mortar of the side of an old house 

 in Suffolk. I have not seen any record of this species utilising 

 snail-shells." 



The Rev. F. D. Morice also informs me that it has been 

 recorded from hollow stems of Heracleum spondylium. 



When the true affinities of the various groups of species in- 

 cluded in Osmia have been determined on structural characters, 

 it will be possible to decide how far the shell -using instinct 

 goes back to a common ancestry, an investigation in which it 

 is hoped that the present collection of records may assist. 



The Rev. F. D. Morice followed with additional remarks 

 on some of the species exhibited. Especially as to Anthidium 

 bellicosum, Lep., and 7-dentatum, Latr., he mentioned a sugges- 

 tion he had formerly made (Tr. Ent. Soc. Presidential Address, 

 Jan., 1913) that there might be a connection between the two 

 facts (1) that, contrary to the usual rule, in these and other 

 large Anthidium spp. the male is larger than the female, and 

 (2) that such species habitually nidificate in ready-made tubes 

 (snail-shells, stems, etc.) of limited dimensions. Too great 

 size would clearly be especially disadvantageous to the ? 

 in such cases, because she would be unable to enter far enough 

 into any but the largest of such receptacles to line and provision 

 them for the reception of her offspring, whereas the <$ need 

 never again enter a tube after emerging from that in which 

 he had originally hatched out. 



In this connection he now referred to a statement he had 

 lately come across in J. H. Fabre's " Souvenirs " that shells 

 utilised by the above Anthidium, spp. contain either one only, 

 or two chambers at most, the inner chamber in such cases — 

 owing to the spiral form of the shell — being of course the 

 smaller. If, as happens in about half the cases observed, the 

 two tenants of such a shell are of different sexes, it seems to 

 be a rule without exception that the inner (smaller) chamber 

 shall contain a $, and the outer (larger) one a <$. 



In answer to a question from Dr. Chapman, he said that 

 these observations did not apply to the genus Osmia. 



