806 REPOBT — 1893. 



a specific virus deposited by the parent cynips, and in attributing to the activities 

 of the living embryos, combined with the normal forces of the plant, the genesis 

 and metamorphoses of the gall ? 



This view has since been emphasised by Dr. Beyerinck, of Utrecht, who, as a 

 deduction from the same facts, holds that in the action of the cynipidae larvae, and 

 not in the injection of a specific virus by the parent cynips, the cause of gall forma- 

 tion is solely to be found. Whether so or not, however, this, at least, may safely 

 be concluded, namely, that while, on the one hand, in those chemical and other 

 forces which produce growth greater activity is induced by the stimulus of the 

 injected fluid — assuming this to be actually present — so, on the other, those 

 mechanical conditions which determine form in organic beings are furnished to a 

 large extent by the contact of the included ovum and by the activities of the 

 embryonic larva. 



Resting in this solution cf the problem, the author proceeds to deal with the 

 facts of parthenogenesis ana metagenesis, as exhibited in the gall-producing 

 cynipidae, and then to trace the operations of phytophagous and entomophagous 

 iuquilines and parasites, 



' The unbidden crew of graceless guests ' ( VirgiV), 



which, season by season, decimate the cynips' larvae, the legitimate possessors of 

 the gall, living on their fatty juices, or so robbing them of their food that they die of 

 poverty and inanition. But here, again, as if to punish wrong and work retributive 

 justice, these inquiline and parasitic enemies in turn are preyed upon by other 

 parasites lower in the scale of creation than themselves, which thin their ranks, and 

 thus, in a rude and barbarous way, maintain the necessary balance of organic life. 



4. On some New Features in Nuclear Division in Lilium martagon. 

 By Professor J. B, Farmek. 



A careful examination of the course of development of the pollen in Lilium 

 inartago7i shows the presence of a varying number of bodies which seem to have 

 escaped the observation of those who have hitherto investigated this plant. To 

 these bodies the general term ' granule ' has been given, as one which involves no 

 assumption as to their real nature. These granules are not easily made clear except 

 by the careful use of selective stains. One of the best methods, though by no 

 means the only one, of sharply differentiating them is that of double staining with 

 haematoxylin and orange G. The great importance of the granules lies in the 

 fact that a variable number of them may become converging points for the achro- 

 matic spindle fibres, and the whole spindle thus becomes multipolar and irregular. 

 This does not, at any rate in the earlier stages of karyokinesis, terminate in any 

 definite granule which may be regarded as a ' centrosome.' This behaviour on the 

 part of the granules obviously affects deeply the whole question of the individuality 

 of the centrosome. 



As to the origin of the granules, it is of extreme interest to find that they 

 appear suddenly in the cytoplasm, which had hitherto been perfectly free from 

 them. Their appearance is immediately subsequent to the fragmentation of the 

 large nucleolus during the preparatory stages of division, and moreover in their 

 staining reactions they exactly coincide with those presented by this structure. A 

 possible connection between the nucleolus and the granules is thus indicated. 



During the later period of division the granules become fewer and larger, but 

 their ultimate fate is not as yet quite clear. 



The above points were illustrated by photomicrographs. 



