May 1893.] 



PSTCHE. 



449 



eral beetles in a cage containing grow- 

 ing peas in which the seeds were about 

 one half grown. Dec. 10, several eggs 

 were laid on the outside of one pod in 

 the same manner as upon the dry seeds. 

 No eggs were laid upon any other pods 

 although there were several in the cage ; 

 and as time passed and the eggs that 

 were laid did not hatch, I began to think 

 that they must have been unfertilized. 

 But as they held their shape and color I 

 left them, and how wonderful has been 

 the result ! The pod ripened, turned 

 yellow, and the vine was nearly killed 

 by plant-lice and mealy-bugs. Finally, 

 in the latter part of January, 1893, I 

 picked the pod and placed it in a box 

 to wait events. After it had been in 

 the box for about a week, I examined 

 it and what was my surprise to find that 

 the brown heads of the larvae were 

 plainly visible through the shells of 

 several eggs. The eggs were hatching ! 

 The pod and its seeds were quite hard 

 and nearly ripened. Fifty days had 

 elapsed since these eggs were laid ; and 

 we have seen that ordinarily on dry 

 seeds the eggs hatch in less than twenty 

 days. 



What unseen hand was it that held in 

 abeyance the development of the embryo 

 in the egg until the pea had reached 

 the ripening stage — the only stage 



when it seems to be fit for the food of 

 the larva? How interesting and won- 

 derful are Nature's ways as revealed in 

 the lives of some of the tiniest of her 

 creatures ! 



Explanation of Plate 16. 



Fig. 1. — Bruchus obtectus Say. 



«, Beetle, enlarged; antenna and leg still 

 more enlarged. (Original.) 



b, Egg, greatly enlarged. (Original.) 



c, First larval stage, much enlarged; 



with leg still more enlarged. 

 (Adapted from Riley.) 



d, Mature larva, enlarged. (Adapted 



from Marlatt.) 



e, Front view of head of mature larva, 



greatly enlarged. (Original.) 



f, Pupa, enlarged. (Adapted from Mar- 



latt. 



g, Infested bean, natural size. (Original.) 



Fig. 2. — Bruchus quadrimaculatus Fabr. 

 «, Beetle, enlarged ; antenna and leg still 

 more enlarged. (Original.) 



b, Egg, greatly enlarged. (Original.) 



c, Basal aspect of egg, greatly enlarged. 



(Original.) 



d, Leg of post-embryonic larva, greatly 



enlarged. (Original.) 



e, Front view of head of mature larva, 



greatly enlarged. (Original.) 

 /"and g. Right wing covers of beetle, 

 showing the variation in size of 

 the adult. (Original.) 

 g to n inclusive, Right wing covers en- 

 larged, showing variation and 

 gradation in coloration. (Original.) 



Hymenoptera of Madagascar. — A nota- 

 ble contribution to entomological literature 

 has just reached this country in the volume 

 treating of the Hymenoptera, forming a part 

 of Grandidier's immense work on the physi- 

 cal and natural history of Madagascar, of 



which it forms vol. xx. The first part is 

 contributed by Dr. H. de Saussure and 

 makes a quarto volume of more than 600 pp. 

 and 27 exquisitely finished plates; the second 

 by Dr. A. Forel on the ants alone, a volume 

 of about 250 pp. and 7 plates. 



