Grub Parasite in the Snail. 



439 



A longitudinal section, slightly enlarged, is given at 3, in 

 order to show the hexagonal shape assumed by the aggre- 



Microgaster alveolarius. 



gated cells ; and Fig. 2 shows the little lids which open to 

 give egress to the insect. All these figures are drawn from 

 specimens in my collection.] 



THE END. 



LONDON: PUINTRD BT w. CLOWES AND SONS, STAMFORD STREET AND 



CHARING CROSS. 



