HARDWICKE'S SCIENCE-GOSSIP. 



139 



stead, N.W. Meets at 8 o'clock on Saturdays at the 

 Hampstead Public Library and Literary Institute, 

 Stansfield House, High Street, Hampstead. 



Harrogate and District Naturalists' and Scicntijic 

 Society : President, Riley Fortune ; Hon. Secretaries, 

 J. Naughton and A. Lambert. Meetings in the 

 Society's Museum Free Library at 8 r.M. every 

 Tuesday from April to September. Field days at 

 intervals. 



Lancaster Science Students' Association : President, 

 H. Wiight ; Hon. Secretary, H. A. D. Jowett. 



SCIENCE-GOSSIP. 



An interesting paper by Mr. H. H. Anderson, of 

 Calcutta, on ^^ Anoplophyra ^olosomatis, a new 

 Ciliate Infusorian Parasitic in the Alimentary Canal 

 oi ^olosoma Chlorostriatum^' has been reprinted. 



We have received a very comprehensive paper on 

 the '■^ Spitiose Rhynchonellce found in England," by 

 S. S. Buckman and J. F. Walker. 



Parts 4 and 5 of Mr. F. A. A. Skuse's useful and 

 interesting papers on "Diptera of Australia" are to 

 hand. Part 4 treats of the families Simulidae and 

 Bibionidse ; part S that of Calcidse. 



Mr. J. A. Wheldon sends us "The York Cata- 

 logue of British Mosses," compiled by himself, 

 " chiefly to supply the place of the London Catalogue, 

 now out of print." The Catalogue seems to be care- 

 fully compiled, and we can heartily recommend it to 

 our muscological readers. 



We have received the Fifth Annual Report of the 

 Watson Botanical Exchange Club. 



It is now four years since Mr. A. E. Shipley called 

 attention in the "Nineteenth Century" to Professor 

 Weismann's Essays on Heredity. In response to 

 the interest which has been aroused, a collection of 

 the Essays has been translated, under the care of Mr. 

 E. B. Poulton, of Oxford, and will form the second 

 volume of the Series of Translations of Foreign Bio- 

 logical Memoirs which the Clarendon Press are 

 publishing. The volume is nearly ready, and may be 

 ■expected shortly. 



" Hampshire Well Sections " is the title of a 

 paper by Mr. W, Whitaker, F.R.S., the President of 

 the Hants Field Club. The article is full of interest, 

 and gives one a good idea of underground Hampshire, 



" On some Physical Changes in the Earth's Crust," 

 by Charles Ricketts, M.D., is an elaborate and read- 

 able paper, reprinted from the "Geological Magazine." 



Dr. Dallinger and John Mayall, jun., are the 

 joint editors of the new edition of Carpenter's 



"Microscope." Dr. Dallinger is responsible for the 

 biological, and John Mayall, jun., for the optical 

 portions of the forthcoming new edition. 



MICROSCOPY. 



New Slides. — We have received from Mr. H. 

 Mellis, of Manchester, two excellently prepared 

 slides — one a transverse section of an embryo rat, 

 illustrating development of bones, &c., and the other 

 of a chick two days old, illustrating development of 

 the eye and optic nerve. 



Species of Pterodina. — I should like to take 

 advantage of Dr. Barnett Burn's article on Pterodina 

 truncata, to state that I have found during the last 

 two years two other species of the same genus, both 

 of which also were discovered by Mr. Gosse, Ft. 

 mucronata and Pt. reflexa (for the latter see the 

 "Journal of the Royal Microscopical Society," 1887, 

 p. 3, pi. i). These two species came from two ponds 

 near Cheadle, Staffordshire. Of the former, I have 

 seen one specimen only ; of the latter, perhaps 

 twenty on different occasions. The "mucro" is very 

 conspicuous in the former when the head is with- 

 drawn ; but in rotation there is little to distinguish 

 it from Pt. patina. Perhaps it is rather more trans- 

 parent ; if I may judge from my one example, it 

 certainly is so. Pt. reflexa is readily distinguished 

 by its elliptical outline and by its small size. The 

 permanent bending upwards of the two halves of the 

 lorica is conspicuous in a lateral or rear view, and 

 makes this pretty little species very distinct. I may 

 point out that Gosse did not describe the eyes of Pt. 

 truncata as "small and transparent," but as "small, 

 remote, and almost colourless." The eyes in his 

 figure seem to me decidedly small. I may perhaps 

 remark here that, unless I was much mistaken, I 

 was more successful than Mr. Gosse in seeing the 

 eyes of Pt. viucronata. I do not think Dr. Burn has 

 really proved that his Pterodince were " in permanent 

 quarters on" the asellus. Indeed, his own words 

 seem to show that they were not. If three of his 

 four examples were "swimming in the water," how 

 could they be permanently attached to the Crus- 

 tacean ? Even if all four had been adhering by their 

 feet, and all four had deposited eggs on the body of 

 the asellus, that would not have proved that the 

 adhesion of the animals was permanent. It is not at 

 all uncommon for some Rotifera, particularly some of 

 the Philodinadce, to adhere for a time to larger 

 animals, such as Crustacese and water-worms ; but 

 this adhesion is often temporary and accidental, and 

 I know of no reason why a Rotifer adhering to a 

 larger animal should not deposit an egg in a con- 

 venient spot on the animal's body, remain near the 

 egg for a time (as Philodina megalotrocha often does), 

 and then swim away.— y. W. Blagg. 



