SCIENCE-GOSSIP. 



117 



and there is plenty of accommodation To reach 

 Shellness one can either walk over the sand-hills — 

 about three miles— or take the train to Sandwich 

 and go to the shore by the path leading to the 

 second coast-guard station —a distance of one-and- 

 a-half miles. This second route is preferable. 

 Sandwich is a quaint old place and well worth 

 visiting for its own sake; it still has the remains of 

 its wall and moat, though the only use of the wall 

 now is to afford a pleasant promenade. The 

 shell beach extends for about two miles from 

 the first coast-guard station, nearly to the mouth 

 of the Stour. A great variety of shells is to 

 be found there. Three short visits to Deal, 

 consisting in all of fifteen days, resulted in a list 

 of 118 species of mollusca, including land and 

 fresh-water species. Among the best finds were 

 Emarginula 1 sea, Scalaria clathratula, Defrancia 

 linearis, Eulima polita, Velutina laevigata, Leda minuta, 

 and Solen vagina. All the British species of Pholas 

 occur, but they are usually only as single valves. 

 A search among the rejectamenta of the Stour, 

 near the ferry on the Ramsgate road, produced 

 Achatina acicula, Hydrobia jenkinsi and many other 

 fresh-water species. Helix cartusiana is abundant on 

 some of the sand-hills near the shore, and on the 

 other side of Deal, near Kingsdown, a large variety 

 of Helix virgata is rather plentiful. — ■/. E. Cooper, 

 93, Southwood Lane, Highgate, N.; April 12th, 1894. 

 Cecidomyia (Diplosis) pvrivora. — This pest 

 has been very destructive in my garden this spring, 

 having destroyed almost the whole produce of 

 some of my pear trees. The kinds which have 

 been most attacked have been Marie Louise, 

 Catillac and Josephine, though other kinds have 

 not been spared. The insect which causes the 

 injury is a very small fly of the same family as 

 some of our most destructive pests, as, for 

 instance, the wheat midge and the hessian fly. 

 The affected pears may be detected very early ; 

 the fly lays its eggs in the blossom, and the little 

 pears thus attacked swell more quickly than the 

 sound fruit, and instead of being pear-shaped are 

 spherical and bloated. On being cut open a 

 number of small larvae will be found in the core. 

 A Yhen they are mature they leave the pears, and 

 falling to the ground bur)- themselves and remain 

 quiescent until the Spring. The life history of 

 this insect has been very carefully investigated by 

 Professor Riley, in America. His account will be 

 found in a Report of the State Entomologist, Charles 

 V. Riley, for the year iSS5, pp. 2S3-2S9. One of 

 the earliest notices in England of the habits of this 

 insect will be found in " A Treatise on Insects," by 

 Vincent Kollar, translated by J. and M.Loudon; 

 and a notice will also be found in the " Ent. 

 Monthly Magazine," vol xxiv., p. 273. Although 

 in all cases the infected pears are misshapen and 

 bloated, yet in some varieties they are small and 

 inconspicuous, as, for instance, in the Josephine, 

 while in others they are much larger, and in the 

 Catillac especially they are very conspicuous. I 

 believe this pest will be found to be common, but 

 as the injured pears soon fall oft" it is doubtless 

 often overlooked. In gardens where the trees are 

 dwarfs or espaliers, it is easy to check or even get 

 rid of this pest. The distorted pears should be 

 collected and burned, or effectually destroyed. 

 This should be done not later than the middle of 

 May, since soon after that time the larva: leave 

 the pears and bury themselves in the earth.— (Rev. J 

 E. N. Bloomfield, Guestling Rectory, Hastings ; June, 

 1894. 





=£? 



BOTANY** v 





Propagation of Anastatica. — I have a very 

 fine specimen of Anastatica hierochuntica, and am 

 anxious to propagate it. What is the best method 

 to adopt for this purpose? — Phoebe Allen, / 

 Bonchurch, Isle <<i Wight. 



[The plant, though it retains its hygroscopic 

 properties, is dead, and cannot be propagated unless 

 the capsules still contain seeds. These might be 

 induced to germinate in a sandy soil.— Eds. S.-G.] 



Potamogetan dndulatus in Ireland. — Mr. 

 Arthur Bennett, F.L.S., communicates to the "Irish 

 Naturalist ' ' the discovery of a dried specimen of this 

 local pond-weed, marked " Six-mile River, Co. 

 Antrim, June 5th, 1882, S. A. Stewart." It seems 

 to be the variety jacksoni of Fryer. He is not 

 aware of any other Irish specimen. 



Alg.e. — In No. 3 of " Science Progress," Mi- 

 George Murry of the British Museum contributes 

 a lengthy article upon the progress of recent 

 knowledge of the Algae. In this article he refer 

 fourteen published papers or more important works. 



North of England Lichens. — The Rev. W. 

 Johnson of Sheldon, Darlington, has undertaken to 

 issue at intervals, in fasciculi of handy form, dried 

 specimens of lichens indigenous to the counties of 

 Northumberland, Cumberland and Durham. These 

 collections will be valuable as a basis for studying 

 this obscure group of plants in connection with the 

 new "Monograph of British Lichens" lately issued 

 by the trustees of the British Museum, which we 

 shall notice in our next issue. 



Fasciated Thistle. — I enclose part of a fasciated 

 example of Carduus lanceolatus which may be worth 

 noting. It looks as though four or five had grown 

 side by side and combined to form one stem of four 

 times the usual width. The flower heads resembled 

 " cocks-combs," bat although the involueral bracts 

 are well developed the florets seem to be wan: 

 There were two specimens of C. lanceolatus in this 

 state growing with the type and C. nutans. C. p\ 

 cephalus, etc., on the slope of a chalk down near 

 Swanage. The two fasciated plants were much 

 shorter than the usual type. — J. E. Cooper, 93, 

 Southwood Lane, Highgate, N. ; June 14/A, 1894. 



Duckweeds. — At a recent meeting of the 

 Linnean Society a paper was read on the habits of 

 three species of Lemna, by Dr. H. B. Guppy. The 

 author gave the results of experiments made bj 

 him during a period of twenty months, and showed 

 that Lemna gibba can pass the winter either in the 

 gibbous form or with fronds, which appear to 

 resemble those of L. minor. The flowering of L. 

 gibba was observed in July, when it was found that 

 the gibbous plants were producing thin flat fronds, 

 which were also in flower, and floating detached. 

 In both cases the flowers were hemaphrodite, but 

 they had the appearance of being unisexual, on 

 account of the flowers of the gibbous plant pro- 

 truding the pistil only, while those of the flat 

 fronds evolved only the stamens. The paper con- 

 cluded with a table of temperatures relating to the 

 germinating, budding and flowering of these plants. 



