HARDWiCKE'S SCIENCE-GOSSIP. 



115 



logue of Plauts" are taken from Watson's Compeu- 

 dium of the " Cybele Britaunica," in whicli work 

 seven lines are devoted to the distribution of each 

 species. If Mr. Stewart will consult this, he will no 

 doubt find what he cannot at present understand, 

 cleared up, as, for instance, that an has slipped 

 out in printing- after the 8, under Uypericim Immi- 

 fasum. — /. G. Baker. 



Seaside Shrubs. — AtriplexHalimus often attracts 

 the attention of visitors to St. Brelade's Bay, in the 

 island of Jersey, by its singular grey foliage. It 

 forms fliere dense hedges, growing luxuriantly in 

 the sandy soil wherever it is planted. It reaches a 

 height of from four to six feet. I am not aware 

 whether it is used in England, but I should think it 

 would grow well on the southern coasts. Certainly 

 there is no difficulty found with the plant in Jersey. 

 Hows of Lavatera are sometimes planted as a garden 

 hedge by the cottagers, though I presume neither 

 that planl nor the still more remarkable Jersey cab- 

 bage, has any claim to be reckoned a "seaside 

 shrub." In Scotland a belt of elder is often used 

 1.0 shelter the seaward aspect of a young plantation. 

 Under the influence of the sea-wind the elder grows 

 dense and bushy. — /. /. M. 



On the Bracts oe Crucifeks.— M. T. Masters, 

 Esq,, M.D., F.R.S., has recently read a paper on 

 this subject before the Linuean Society. The sub- 

 ject was divided by the writer into two branches : 

 -7-1. The absence of bracts in Crucifers. In the 

 majority of cases this is so complete that even in 

 the earliest stages of development observed by Payer 

 no trace of bracts is seen. Different explanations 

 of the phenomenon have been given by different 

 morphologists. A. P. de Candolle attributes it to 

 congenital suppression of the parts ; Godron to 

 pressure acting from within outwards, resulting from 

 the dense manner in which the young flowers are 

 packed together ; Norman and Eichler consider that 

 the bracts are abortive, but potentially presents 

 the latter writer combating Godron's view by the 

 consideration that on the one hand the bracts are 

 absent where the inflorescence is so loose that no 

 pressure can be exerted, and, on the other hand, in 

 some cases where the flowers are densely crowded 

 the bracts nevertheless exist. 3. The occasional 

 presence of bracts in Crucifers. About fifty illus- 

 trations of this were named. A few species, as 

 Sisymhrivm suphmni and Jdrsutum, have normal 

 bracts to every flower ; in others their occurrence is 

 only occasional. Where the raceme shows a tendency 

 to branch into a panicle, they may often be found at 

 the base of the secondary divisions of the inflores- 

 cence ; in Arabis turrita the lowermost peduncles 

 have bracts at their base; the intermediate ones 

 have bracts springing from their outer surface above 

 their base, while the uppermost have none at all. 



The writer then discussed the various theories which. 

 have been proposed to account for the variation in 

 the position of the bracts when present ; viz. at the 

 base or on the side of the flower-stalk above the 

 base. The causes assigned for the latter apparently 

 anomalous position were stated by different botanists 

 to be the following : — 1. Partition or subdivision of 

 the axis ; 2. congenital union, or lackjof separation 

 between the bract and the pedicle ; 3. upraising of 

 the bud and its bract. Anatomy gives no evidence 

 of partition ; but it does afford in some cases the 

 evidence of fusion, or rather of inseparation, as 

 in some of the Crucifer/iE examined by Dr. Masters ; 

 while in the case of Sedum, Solaiiiim, and Spiraea 

 the peculiar arrangement of the bract seems to be 

 owing to the third cause above mentioned. 



Fauna and Flora of Eastbourne.— We have 

 received a copy of the supplement to the Fauna and 

 Flora of Eastbourne, by F. C. S. Roper, F.L.S., 

 printed for private circulation. Both the supple-- 

 ment and the original work were undertaken by the 

 chief members of the Natural History Society. The 

 lists are numerous, and the work altogether well 

 done. It is impossible to award too much praise 

 to those who have been engaged upon it, and to 

 whom it has evidently been a labour of love. 



British Marine AlgyE.— Mr. W. H. Grattann's 

 work on the above subject has now reached the sixth 

 part, including 133 illustrations. We regard this as 

 the cheapest and moat trustworthy yet offered to 

 the pubUc, and it is especially suited to the wants 

 of young students of our British sea-weeds. The 

 price of each part is only sixpence. 



Eucalyptus globulus (Blue Gum-tree).— 

 Some of the various notices which have appeared 

 regarding this tree would lead to the supposition 

 that its extraordinary sanitary properties are pro- 

 duced by exhalations from the flowers or leaves, 

 which contain an astringent gum, and yield on dis- 

 tillation an essential oil. It is called a " disease- 

 destroying plant," from its supposed emission of 

 " antiseptic camphorous effluvia," and because it is 

 found that, when planted in swamps, marshes, and 

 other dainp spots, it removes the malaria common 

 in such pestiferous regions. It appears to me, how- 

 ever, that its effects may be attributed simply to 

 drainage, by absorbing the moisture of the soil by 

 its roots, and evaporation by the leaves, as stated 

 by T. J. E. in Science-Gossip for March, who says 

 he has had many years' experience in its cultivation, 

 and refers to the "pumping power exerted by the 

 far-spreading roots of this gigantic tree." The 

 latter hypothesis would lead to the conclusion that 

 the process is entirely mechanical, and that any 

 other large trees, having roots as extensive, with 

 similar powers of absorption and evaporation, and 

 of a nature to thrive in swampy regions, would have 



