HARDWICKE'S SCIENCE-GOSSIP. 



249 



are constantly in motion. It has a small red eye, 

 situated a little above the mastax. Its head is 

 projected a good distance beyond the front of the 

 lorica. The corona is formed by three rounded lobes 

 with a tuft of long vibratile cilia on each lobe. It is 

 a vigorous swimmer. The head is contracted swiftly 

 within the lorica on the approach of danger, and at 

 the same instant the lateral spines are projected. 

 With its head drawn within the lorica the creature 

 is protected by the six frontal and the two lateral 

 spines. 



The water vascular system is conspicuous in 

 specimens that have been kept for a few days in a 

 jar of clear sea water, as the creatures then become 

 very transparent, thus permitting a clear observation 

 of the lateral tubes and vibratile tags ; which lead to 

 a large contractile vesicle near the posterior. 



through a conical calico bag a large quantity of water 

 dipped from amongst weeds at the sides and bottom 

 of tide pools, and then fill a wide-mouthed bottle 

 with the remains. 



Length of full-grown 

 mens ^ of an inch. 



Dundee. 



specimens S j, young speci- 



John Hood, F.R.M.S. 



Fig. 134 — a, Dorsal view of NotJwlca spinijera, 

 with lateral spines extended. 



Fi?. 135. — Side view of 

 Nothoka spinifera. 



I found the N. spinifera for the first time in a tide 

 pool in the estuary of the Tay (November, 1885), 

 associated with Syncheeta tallica, Pterodina clypeata, 

 and Mytilia Tavina ; and have fished it up frequently 

 since at all seasons, both in the cold winter months 

 ar.d in the heat of summer, in various parts of the 

 Tay ; but its habitat is by no means confined to the 

 east coast of Scotland, for in July this year (1887), 

 Mr. Boyd, of Glasgow, sent me a bottle of water he 

 had dipped from a tide pool in Loch Long (an arm 

 of the sea on the west coast), which contained a 

 number of specimens of N. spinifera in a healthy 

 condition. It does not carry its egg after expulsion, 

 but deposits it on the alga and conferva at the bottom 

 of the pool. It is a hardy rotiferon, and can be kept 

 alive in a marine aquarium for months. 



The best way to collect marine rotifera is to filter 



NOTES ON NEW BOOKS. 



'J^HE Geology of England and Wales, by II. B. 

 J. Woodward, F.G.S. Second ed. (London: 

 George Philip & Son.) It is now ten years since 

 Mr. Woodward's manual first appeared. It took a 

 leading place in geological literature at once, and 

 has kept it ever since. Of course, 

 within the last decade, geology has 

 considerably extended its boundaries, 

 so that much more has to be said on 

 the geology of this country now than 

 could have been said in 1877. Mr. 

 Woodward has accordingly brought out 

 a new edition of his valuable book, in 

 which all the new matter is included. 

 Practically this second edition is a new 

 and re-written book, nearly double the 

 size of its popular predecessor. We 

 are pleased, however, to observe that 

 the original plan of the work has not 

 been altered. It would have been very 

 difficult indeed to have altered it for 

 the better. One of the most valuable 

 chapters, to the geological student, is 

 that which deals with the numerous 

 researches in the Archaan rocks which 

 have been made within the last ten 

 years. Also, the details of the sub- 

 divisions of the Cambrian and Silurian, 

 old red sandstone and carboniferous, as 

 well as of the oolitic formations. The 

 eruptive and metamorphic rocks naturally come in for 

 much extended notice, thanks to the application of the 

 microscope to rock structures. Mr. E. T. Newton's 

 valuable synopsis of the animal kingdom appended 

 to this work has already been noticed in our columns. 

 A capital geological map of England and Wales, 

 24 inches by 195, is included. Altogether, we 

 heartily congratulate Mr. Woodward on the greatly 

 advanced and improved tone of the second edition. 

 It will henceforth be above criticism, for it is a 

 book which critics themselves will be obliged to 

 consult before criticising. 



Manual of Bacteriology, by Dr. E. M. Crookshank, 

 second edition, revised and enlarged (London : 

 H. K. Lewis). This is another important work which 

 appeared less than three years ago, and, large as the 

 volume then was, it has swollen to nearly double its 



