( 177 ) 

 PEOGEESS OF MICEOSCOPICAL SCIENCE. 



Fungous Growths in Mollush Shells. — In a paper read before the 

 Manchester Philosophical Society on the 26 th of February, Mr. Mark 

 Stirrup exhibited sections of shells of mollusca, showing so-called 

 fungoid growths. He referred to Dr. Carjjenter's report on shell 

 structure, presented to the meeting of the British Association in 1844, 

 in which esjiecial mention is made of a tubular structure in certain 

 shells, and he cites the A^iomia as a characteristic example. In the last 

 edition of ' The Microscope,' Dr. Carpenter, he said, withdraws his 

 former explanation of this structure, and now refers it to the parasitic 

 action of a fungus. Mr. Stirrup showed sections of this shell pene- 

 trated by tubuli from the outer to the inner layers of the shell, and it 

 is upon the inner layer that the curious appearance of sporangia, with 

 slightly-branched filamentous processes proceeding from them, present 

 themselves. The parasitic view is strengthened by the fact that these 

 markings are not found in all parts of the shell, and are certainly ac- 

 cidental. Professor KoUiker maintains the fungoid nature of these 

 tubuli in shells as well as in other hard tissues of animals, as fish scales, 

 &c. Wedl, another investigator, considers the tubuli in all bivalves 

 as produced by vegetable parasites, and that no other interpretation 

 can be given. This view does not seem to be borne out by the sec- 

 tion of another shell which was exhibited, '^Arca navicula," in which 

 the tubuli are always present forming an integrant part ; they are 

 disposed in a straight and tolerably regular manner between the ridges 

 of the shell; moreover, they have neither the irregularly-branched 

 structure nor the sporangia. 



A Conspectus of the Diatomacece. — The ' Lens,' which is the quarterly 

 journal containing the Transactions of the State Microscopical Society 

 of Illinois, has at length, after long delays, caused of course by 

 the terrific fire at Chicago, made its appearance. We must congra- 

 tulate the Editor and Publishing Committee upon the fact. Of 

 course it was difficult to get out a first number in a place so grievously 

 injured by fire as Chicago ; still it is a very good number, and we have 

 no doubt that its successors will surpass it in excellence. The most 

 important paper is one taken from the ' Monthly Microscopical Jour- 

 nal,' and it too is the only paper which possesses a plate, also taken 

 from the ' Monthly Microscopical Journal.' Still there are some good 

 essays, and among them is that whose title heads this paragraph. In 

 this the author, Professor H. L. Smith, of Hobart College, N.Y., 

 attempts to give a synopsis of the names of every genus of the Diatom- 

 aceae, and the arrangement is apparently excellent. The explana- 

 tion of the terms in use is a good one. It seems to us though that the 

 author would have done better had he admitted fully the appearance 

 of striffi as only an apparent structure that microscopic observation 

 tended to show was merely a linear arrangement of dots or hemi- 

 spheres. 



