HA RD WICKE' S SCIENCE- G OS SIP. 



275 



convex. Toe of moderate length, straight and 

 terminated by two diverging, curved and seemingly 

 immovable claws. 



When extended, this species is rather like M. 

 mollis, as figured by Mr. Gosse, but the bifurcate toe 

 distinguishes it readily from that, and from every 

 ■other species yet described. It can scarcely be said 

 to possess a lorica. save that it assumes in retraction 

 a definite broadly ovate outline. The internal organs 

 seemed normal. The head is stout, but tapering 

 and rounded in front, above the almost prone face, 

 and an ample brain descends behind the mastax, 

 bearing a very conspicuous eye. The trunk, both in 

 dorsal and lateral view, presents a slightly waved 

 outline. The foot-joints are stout, the lower rather 

 broad for its length, and the toe, almost parallel- 

 sided viewed from above, is seen in lateral aspect, to 

 taper gradually from the base. There seemed to be 

 a slight median depression on the toe, just above the 

 tip, but not a definite line, such as would indicate the 

 soldering together of two toes. 



Three specimens only of this peculiar form 

 occurred in moss stripped from a branch partially 

 submerged in a ditch near the Waterworks, Sandown 

 (I.W.), in August, 1S91. Length, extended, esti- 

 mated at s^j inch. 



It swims quietly and steadily, or crawls about, 

 nibbling as it goes, and contorting itself violently all 

 the while. 



Monostyla galeata, n. sp. 



Sp. Ch. — Ovate in outline. Lorica distinct 

 without markings ; in retraction anterior margins 

 nearly straight ; head furnished with protrusile shield, 

 hook-like in lateral view. Toe styliform, of moderate 

 length, shouldered, with single claw. 



I found numerous dead examples and empty loricoe 

 among washings from sphagnum, gathered in July 

 and August, 1S91, at Sandown (I.W.), but passed 

 them by, as beiDg probably a small variety of M. 

 lunaris, distinguished by its smaller size, and its 

 straight anterior margin of lorica in retraction. 

 Some months later I found, in a washing from the 

 same moss, a living specimen, and I then discovered 

 that it possessed the striking peculiarity of a frontal 

 shield-like hood, exactly like that figured by Mr. 

 Gosse in Colurus. 



I was unable to get a good view of the internal 

 structure, as the creature was very lively, and shortly 

 after its discovery was lost at the edge of the cell. I 

 found later, that a dead specimen which I had 

 preserved, showed the hood half protruded. 



The dorsal plate is, as in most of the Monostyloe, 

 broader than the ventral. The shield-plate is broad 

 and rounded behind, while the hinge-plate shows 

 the usual parallel lines, and the lower foot-joint is 

 rather bead-like in outline. Length, about 2 -Jnj inch 

 extended ; toe and claw, about g^j inch. 



CASUAL AND ALIEN PLANTS. 



ATTENTION having been called in a recent 

 number of Science-Gossip, to the occurrence 

 of Ornithosis roseus and Coronilla varia in a sub- 

 spontaneous manner, I beg to enumerate a few more 

 examples of casual plants which have come under 

 my own personal notice. These have mostly been 

 noticed in short rambles near large towns, where 

 business pursuits prevented botanising in the country, 

 except at long intervals. A few instances only are 

 mentioned of casuals in the more rural districts. 

 Eranthis hyemalis, Salisb., perpetuates itself in a 

 plantation near Crosby Court, North Yorkshire, 

 where it may, however, have been planted. Papaver 

 somniferum, L., is a frequent casual at Scarborough, 

 Aintree (Lancashire), and about York, but is always 

 sporadic in its appearance. Corydalis iutea, grows in 

 profusion on walls at Arden Hall, a bleak spot on the 

 Hambleton Hills, evidently escaped from the hall 

 garden. Arabis arenosa, Scop., occurred casually and 

 sparingly on waste ground at York. Hesperis matro- 

 nails, L., on rubbish-heaps at Aintree. Sisymbrium 

 pannonicum, in some quantity on Foss Islands, York, 

 where it may establish itself as it has done about 

 Hightown and Crosby, Lancashire. In the latter dis- 

 trict it has more than held its own for many years. Ery- 

 simum perfoliatnm, Crantz ; grain-brought at Walton, 

 Lanes. E. repandum, on ballast near Birkenhead 

 docks, Cheshire. Camelina fectida, impermanent alien 

 at Northallerton, York, and Leeds, and C. saliva, 

 Crantz, on waste heaps at Aintree. Brassica 

 Erucastrum, Vill., on ballast at York. Diplotaxls 

 tenuifolia, D.C., on rail embankments at North- 

 allerton and Thirsk, where it may establish itself; 

 also in similar situations at Tyne Dock, near South 

 Shields. Lepidium sativum, L., a frequent garden 

 outcast, as also Raphanus salivus, L. Diantlius 

 plumarius, L., grows on the ruins of Fountains 

 Abbey, where it may have been intentionally planted. 

 Saponaria vaccaria, L., a few plants at York, and 

 more plentifully at Hightown and Aintree. An 

 increasing species with us, introduced with grain. 

 Silene dichotoma, L. , was found by Mr. Geo. Webster 

 in cornfields near York, and I have gathered what 

 appears like a form of the same thing in some plenty 

 on ballast at Aintree. Claytonia perfoliata, Don., 

 occurs in a plantation and surrounding lanes near 

 Formby, to all appearance thoroughly established. 

 Malva borealis, Wall., M. nicasneis, All., and M. 

 parviflora, Huds., grew together in some abundance 

 where flour-mill refuse was out-thrown at York, and 

 a plant or two of M. Alcea, L. , were found many 

 years ago at Northallerton, by a roadside. Linum 

 usilalissimum is a frequent casual. It was formerly 

 extensively cultivated near Northallerton, when it 

 was occasionally infested with its parasite, Cuscuta 

 epilinum. A variety with many stems, and carpels 

 ciliate internally, occurred this year at Aintree, and 



