HA RD WICKE'S SCIENCE- G OSS IP. 



i8s 



authentic specimens of H. similis, which even at that 

 period was fast becoming extinct as a British species, 

 and it was the result of having to depend only upon 

 general description, and obscure figures of species 

 only. I believe Mr. Crouch must be mistaken in his 

 impression "that further notes appeared in the 

 Journal of Conchology for 1889, showing that the 

 form had already been taken at Greenwich two years 

 before (1887)." To the best of my belief the species 

 had long since disappeared from the locality. In 

 looking over my diary I find my last record of their 

 being taken alive at East Greenwich marshes is 

 July 4th, 1SS5, and subsequent search has failed to 

 discover a single specimen in that district. I am of 

 Mr. Crouch's opinion that the creatures have been 

 introduced from abroad, and judging from the fact 

 that they only appear to inhabit a few ditches at 

 Beckton, and do not occur elsewhere in the Essex 

 marshes, while they abound upon the south side of 

 the river, and have been taken in abundance from 

 ditches, commencing at the arsenal, and extending 

 away down the river to a point midway between 

 Darenth Creek and Greenhithe ; I am inclined to 

 think they were first introduced upon this side of the 

 river, probably at or near East Greenwich marshes. 

 I am confirmed in my opinion by the fact that the 

 species does not appear to have been taken at Beckton 

 previous to 18S9, whereas it has been proved that 

 they abounded all over the Plumstead marshes at 

 that time, and were collected by me nearly six years 

 before at Greenwich. How, or when, or where they 

 were first introduced may always remain a mystery, 

 but surely sooner or later the species will be discovered 

 abroad. Professor E. von Marten, of Berlin, to 

 whom in 1890, I sent specimens for the Berlin 

 Museum, wrote me as follows :— " I thank you very 

 much for the Hydrobire, which are very interesting 

 for me ; I know none which may be identical with 

 it, in any part of the world. Pototnopyrgus antipo- 

 dium, Gray, from New Zealand, has a similar ridge 

 below the suture, but this is often spinous, and it 

 differs in other regards. I shall place most of your 

 specimens in the Berlin Museum." One variety of 

 this antipodean species in my collection strongly 

 resembles H. Jenkiiisi, but is scarcely identical with 

 it, and the typical shells differ very much indeed. 

 — H. y. Jenkins, M.C.S., New Cross. 



BOTANY. 



Albino Flowers.— In reply to Mr, Stewart's 

 queiy, I am able to state that I have found albino 

 flowers of Erica tetralix on one or two spots on the 

 extensive heaths surrounding Aldershot. As it may 

 be of interest to some of your readers, I here append 

 a list of the Albino flowers I have at present in my 



collection. Trifoliuvi pratense, Epilobiuin hirsiitiim, 

 Epilobiiim tno7itanui)i, Calhnia vulgaris. Erica 

 tetralix, Ccntranthus ruber, Centaiirea scabiosa (this 

 sometimes occurs with white ray florets and purple 

 disk florets), Scilla nutans, Erythrcea centauriiim. 

 Salvia vcrbenaca (foreign). Origanum znilgarc. Thymus 

 se)-pyllitm, Prunella vulgaris, Lamium purpuretim, 

 Ajuga reptans, Cnicus palitstris. Orchis morio. Orchis 

 maculata, Campanula rotu7idifoHa, Dianthiis plu- 

 marius, Geranium pusillum, Fritillaria nieleagris, 

 Veronica agrestis, Vicia satira, Zi/iaria cymbalaria. 

 Primula vulgaris. — E. Armitage. 



Lemna trisulca, &c. — In June, on a Botanical 

 ramble I dipped into a small pond, to inspect the 

 plants growing there. On examining the Lemnse, as 

 I always do, to my great surprise I found Lemna 

 trisulca unmistakably in flower. The flowers in 

 ever}' case existed on fresh young growths, never on 

 any of older, fully formed leaves. In no other place, 

 nor in this before, have I ever found these young 

 growths, and never a single flower ; but now I find 

 myriads, and have observed them every way, by eye 

 and under microscope. L. gibba seems to bloom here 

 every year. — ]V. 0. Wait, Rugby, 



Erica Mediterranea in Cornwall. — Referring 

 to the statement in Mr. Nower's interesting descrip- 

 tion of a " Ramble near Roundstone," that a spot in 

 Galway, and one in Mayo, are the only British habitats 

 of Erica mediterranea, I would take the opportunity 

 of saying we have a specimen of this plant growing 

 here in the Kennall Valley. It is a particularly fine 

 plant, about five feet in diameter, and grows on the 

 highway from Truro to Falmouth amid a brake of 

 wood spurge, heather, and periwinkles. Its locale 

 is closely adjacent to one of the branches of the Fal, 

 but whether it owes its existence in this valley to the 

 " rolUng restless waves," or whether it was originally 

 an inhabitant of one of the neighbouring estates, I 

 leave an open question. One thing, however, is 

 certain, that is, the plant has flourished here for 

 upwards of thirty years. Not far from it its con- 

 gener. Erica ciliaris, grows in all its glory. — Fred. H. 

 Davey, Poiisanooth, Perran-ar-zuorthal, Cornivall. 



An Abnormal Strawberry. — Perhaps you may 

 care to insert the following note, if for the sake of the 

 curious shape, in Science-Gossip. I saw it to-day 

 amongst some strawberries I purchased. I have 

 seen double and treble strawberries before, but 

 never one that seems to be made up of six or seven, 

 — I think seven, for one division is already decaying, 

 but looks as if it had been in a way separate, while 

 the leaves of the calyx at the back are very numerous. 

 Perhaps, however, some of your correspondents may 

 be able to tell us of oddities as strange among 

 strawberries. This one comes from the suburbs of 

 Bath, I imagine. — F. S. HolUngs. 



