496 RECORD OF CURRENT RESEARCHES RELATING TO 



other to form a real network ; wlien torn they curl up at the ends. 

 They do not swell up when treated with acids, and they yield 

 elastin." 



Part I. is entitled Practical Histology, and Part II. Physiolo- 

 gical Chemistry ; some more difficult subjects are dealt with in the 

 Appendix, which concludes with Mr. Groves' valuable classification of 

 staining fluids, and a copy of Messrs. Parkes's table of the magnifying 

 powers of Microscopes. 



Collecting and Mounting Spiders' Webs.* — Mr. J. Fenner, refer- 

 ring to Mr. Hind's paper on this subject (ante, p. 320), thinks that not 

 so much has been made of the subject as it is capable of, and gives 

 his own exiDerience. It occurred to him that he would endeavour to 

 view a web with a light in front to answer for direct sunlight, and 

 another behind to rej)resent sunlight reflected back from the surface 

 of green foliage. To imitate these conditions, the lamj) is placed in 

 front and on one side of the stage of the Microscope, using the bull's- 

 eye condenser to focus on to the web. Then take a piece of stout 

 millboard, covered with a bright green paper, bent into a semicircular 

 form to back the lamp, so placed that the green light from its surface 

 shall fall on the mirror beneath the stage, and be thrown back from it 

 through the web. There is no slide, or covering glass, or mounting 

 medium of any kind ; but as the webs are entirely exposed, it is, of 

 course, necessary to keep them free from dust, &c. As the threads of 

 a web are, in their natural form, at some considerable distance apart, 

 you can, in the ordinary way, only get one or two lines into the field 

 of view at one time ; the web should therefore be doubled and 

 quadrupled. In order to accomplish this, take a piece of thin board, 

 such as cigar-boxes are made of, about 10 inches by 6 inches, and cut 

 out the middle part, leaving a margin ^ inch wide, which smear on 

 one side with thick gum. Then, j)lacing the frame behind a clean, 

 newly-formed web, and bringing it forward gently, and cutting away 

 all round, transfer the web bodily on to the frame. In order to 

 double the web cut another frame, about 8^ inches by 4^ inches, and 

 take a second web. Then placing the smaller frame on a table, bring 

 down the larger one so as to cover and include the other, and then 

 cutting away between the two, a doubled web is obtained. If this is 

 not sufiicient a still smaller frame should be made and the operation 

 repeated. When a web is thus obtained with as many lines close 

 together as is required, take some small disks of thin cardboard with 

 ^-inch centres punched out, and having gummed them, place them 

 both before and behind the web, and in this way obtain small portions 

 of the most suitable parts of the web which can be placed on the stage 

 of the Microscope. 



Koch's Method of Preparing Sections of Corals.f — Mr. H. N. 

 Moseley testifies to the great success of this method, which was de- 

 scribed in a previous volume. J In some sections of corals sent him 



* 'Engl. Mech.; xxxi. (1880) p. 135. 



t 'Quart. Journ. Micr. Sc:.,' xx. (1880) p. 245. 



X This Journal, i. (1878) p. 274, 



