1854.] Linnean Society. 335* 



the grubs or young bees ; but about a fortnight after the work just 

 described has been finished, the nests are all found to be burst 

 through, and the fragments of the shell and casing of the chrysalis 

 are found inside. I have watched these operations frequently at 

 Bombay, and only regretted that the pressure of other avocations 

 prevented me from gathering more jjarticulars than I have now 

 given. So far as they go they may be relied on." 



Read also a paper " On some remarkable Spherical Exostoses 

 developed on the Roots of various species of Coniferee." By Joseph 

 Dalton Hooker, Esq., M.D., F.R.S., F.L.S. &c. 



Dr. Hooker states that the exostoses which form the subject of 

 his paper were first observed by him on the roots of the Podocarpus 

 dacrydioides of New Zealand, collected bj^ the Rev. W. Colenso ; 

 and subsequently at Kew, in company with the Rev. M. J. Berkeley, 

 he found similar organs to be of very general occurrence among 

 ConifercB. As examples he mentions Araucarice of several species, 

 Podocarpi, Taxodium, Dacrydium, Thvja, Cupressus, Phyllocladus, 

 and Cunning hamia. Mr. Berkeley has described, in the ' Gardeners' 

 Chronicle,' exostoses on the roots of the Pea, and Dr. Hooker has 

 also been long familiar with other examples, especially with a most 

 remarkable modification of them on the Laburnum, pointed out to 

 him by Prof. Henslow, who has also shown him others on the Gar- 

 den Bean, and on species of Lathyrus, both wild and cultivated, as 

 well as on other Leguminosce. Except, however, in the instance of 

 Taxodium distichum, in which they have been noticed by the elder 

 DeCandoUe (' Theorie Elementaire,' Ed. 2. p. 356), and in which 

 they exist in a very peculiar condition, he is not aware of their pre- 

 valence in Coniferee having been anywhere noted. In Podocarpus 

 dacrydioides, the species selected for illustration, the roots and root- 

 lets are studded at intervals with spherical bodies, of diameters 

 varying between the ^^th and -^th of an inch, either attached by 

 a very short pedicel, or absolutely sessile, and sometimes even sunk 

 into the bark of the root. They are easily detached, leaving a small 

 scar, are of a soft and spongy consistence, smooth and even on the 

 surface, of a pale reddish colour, and in a vertical section are seen 

 to be composed of — (1) a mass of spongy cellular tissue, aggregated 

 round (2) a central vascular axis, which extends from the wood of 

 the root to the centre of the sphere, and (3) a delicate cuticle. 

 Each of these tissues is described in detail, and illustrative figures 

 of the exostoses of P. dacrydioides and of their microscopic anatomy 



