400 Notes and Memoranda. 



Annals of Natural History, and promises shortly a paper to show the, " organic 

 unity " of the basal mass of sponge tissue, the spicular axis or rope, and its 

 coriaceous envelope. 



Deep Sea Liee. — Annals of Natural History contains a report by Mr. George 

 Jeffreys on Dredging among the Hebrides, in which he states that Professor Sars 

 is of opinion that Dr. Wallich's deep sea star fish is an OpMocantha spinulosa, a 

 well-known Greenland species, found usually from 20 to 190 fathoms depth. 

 He states that Professor Sars has enumerated fifty-two species and distinct 

 varieties of animals found by himself at a depth of 300 fathoms — sponges, rhizo- 

 pods, actinozoa (anemonies), polyzoa, true mollusks, and worms. The Swedish 

 deep sea dredgings, in the expedition to Spitzbergen (1861), sounded depths of 

 from 6000 to 8400 feet (1000 to 1400 fathoms), and the sea bottom at these 

 depths was covered with a fine greasy-feeling material of a yellowish-brownish or 

 grey colour, rich in diatomacea ; and polythalamia, annelids, Crustacea, and 

 mollusca were found at these depths. 



Me. Pearson's Photomicrographs. — Mr. Pearson has published, through 

 Mr. Frederick J. Cox, a series of photographs of microscopic objects taken with 

 the lime light. Most of those we have seen are exceedingly good ; salicine and 

 cinchonidine under polarized light, sections of sarsaparilla, pepper, cherry-tree 

 wood, coal, lime-stone from the Himalayas, and oolite are very beautiful speci- 

 mens of this ingenious art, excellently displaying the peculiarities of the several 

 objects. A slide of foraminifera seems to be less successful, and the trichinae 

 spirales have not come out with sufficient distinctness. Others, which we have 

 specified, occupy a high place among works of this kind, and show how valuable 

 the photographic process is to give accurate delineations of objects extremely 

 troublesome to draw anything like as well. 



New Edition oe " The Heavens." — A subscriber calls our attention to Mr. 

 Bentley's advertisement of a new edition of The Heavens, with " sixty illustra- 

 tions," and asks what number the last French edition contains. On referring 

 to our French copy we find 40 plates, and 192 engravings incorporated in 

 the text. We can give no information as to what Mr. Bentley includes in the 

 " sixty" he announces, but we observe that he wants as much money for his 

 edition as the complete French one costs. 



