260 



HARDWICKE'S SCIENCE-GOSSIP. 



[Nov. 1, 1S6S. 



MICROSCOPY. 



Dipping-Tube. — Allow me to call attention to 

 a form of dipping-tube that has been 

 extremely useful to me this season, and 

 which I feel sure will be found to have 

 many advantages over the simple glass 

 tube in general use. It consists of a piece 

 of glass tube (a) from three to five inches 

 (or more) in length, and about quarter- 

 inch bore, to one end of which a piece 

 of indiarubber tubing (b) about half the 

 length of a, and of sufficient bore just to 

 admit the glass tube, is fastened, by bind- 

 ing thread tightly round, as at c; the other 

 end of b is stopped with a small plug of 

 wood, aud also tied with thread as at d; 

 the action of which, by pressure of the 

 thumb and finger, is too simple to need 

 description. Any quantity of liquid can 

 be introduced and expelled at will, or be 

 retained in the tube until required for 

 examination, without the inconvenience of 

 being (as before) compelled to keep one 

 end stopped with the finger. In extremely 

 shallow water, the advantage is very 

 sensibly felt, and 1 trust will prove useful. 



Fig. 246. — H' Daltoti. 



A" [House-fly {Anthomyia pluvialis). — \ have 

 •often observed, especially during the past summer, 

 a large number of a species of fly, mixed with the 



FiS. 247- Anlhuniyiti pluvialis. 



common house-fly in the windows of shops and 

 private houses around the metropolis. This is 

 determined as a species of Anthomyia, named above, 

 which is said to be the forerunner of rain ; hence its 

 specific name. It is about the same size as the 

 common house-fly, perhaps not quite so large, paler 

 coloured, and more distinctly marked, as will be 

 seen from the figure. What appear to me to be 

 the eggs of this species are beautiful microscopical 



objects, long and narrow, covered with hexagonal 

 pits, and with a wing-like expansion on each side 

 throughout the entire length, reticulated in a 

 similar manner but with shallower pits. — M. U. S. 



Journal of the Royal Microscopical 

 Society. — The Royal Microscopical Society having 

 ceased connection with the Quarterly Journal of 

 Microscopical Science, in which for sixteen years 

 their Transactions have been published, have an- 

 nounced to the Eellows their intention of publishing 

 their own journal in future, under the editorship of 

 Dr. Henry Lawson. Messrs. Churchill have also 

 made the announcement that the Quarterly Jotrrnal 

 of Microscopical Science will continue to be pub- 

 lished by them as heretofore, without any change in 

 the editorial department. 



Deep Sea Dredging in the Gulf Streaii. 

 — At the meeting in August of the United States 

 National Academy of Sciences, a paper was read by 

 Count Pourtales, who has recently been employed 

 by the Coast Survey to dredge the bottom of the 

 ocean along the course of the Gulf Stream, in 

 parallel lines, crossing the current, the lines being 

 about ten miles apart. In starting south-easterly 

 from Elorida, he found the bottom for four or five 

 miles made up of the common coral sand of that 

 neighbourhood, with very scanty traces of life. The 

 next area, from 90 to 300 fathoms, and the first 

 part of the way forming a plateau, is a rocky floor, 

 made of very hard limestone, derived from living 

 shells. Life was abundant, consisting of lamp- 

 shells, starfishes, crustaceans, and molluscs gene- 

 rally. There were also many bones of the manateo, 

 a dolphin-like animal, usually found living in shallow 

 water. The third area was the regular and common 

 ocean-bottom, from 250 to 300 fathoms, covered by 

 the chalky remains of foraminifera — those minute 

 animals found several years since on the telegraphic 

 plateau in the North Atlantic. He also exhibited 

 a map of the bottom of the ocean off the coast, and 

 found first, extending from the north of Elorida to 

 Montauk Point, near Block Island, Rhode Island, a 

 bottom of siliceous sand, perhaps 100 miles wide. 

 Outside of it was a calcareous bottom, occupying 

 the whole area south of Georgia. Between the two, 

 off the Carolinas, is a limited deposit of green sand, 

 containing the foraminifera. A letter was read 

 from Professor Agassiz, w r armly eulogizing Pour- 

 tales' papers, and saying that he had solicited the 

 honour of publishing the maps and other results in 

 one of the volumes issued at the Museum of Com- 

 parative Zoology in Cambridge, Massachusetts. It 

 opens, he said, an entirely new chapter in natural 

 history. It disclosed what had never been before 

 known, the various fauna at the bottom of the 

 ocean. Among the animals obtained were some 

 that had been extinct since the cretaceous and ter- 

 tiary periods. — Neic York Times. 



