ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



717 



shown in figs. 144 and 



Fig. 145. 



The lung P being dissected out is placed as shown in figs. 141 and 

 143, and is covered by a cover-glass held in a ring A which can be 

 raised or lowered by the rack and pinion C, and the surface can be 

 reduced to a plane. 



Kanvier's apparatus for the mesentery,* 

 145, consists simply of a plate L with 

 an aperture, over which is attached a 

 cork disk B, having a hole drilled through 

 the centre so as to allow light to be 

 transmitted from the mirror. The in- 

 testine is dissected out and attached to the 

 disk as shown in the figure. If it is not 

 thus elevated above the level of the wound, 

 blood and lymph will run out and hinder 

 observation. To fix the intestine and 

 mesentery, the disk B has its upper surface 

 cut away so as to leave an annular pro- 

 jection in the centre, on which the mesentery M rests and round 

 which the intestine I is placed. 



Another arrangement | is shown in fig. 146. A wooden or ebonite 

 plate, to carry the frog, has a circular aperture, over which a glass 

 slide is supported on two corks or pieces of ebonite about l-6th in. 



Fig. Ue,. 



deep. The slide is covered with cork l-8th in. thick, having a semi- 

 circular piece cut out in the centre. In the middle of this, and just 

 over the aperture in the bottom plate is a glass disk, l-8th in. thick, 

 on which the mesentery lies, the space between it and the cork form- 

 ing a trough for the reception of the coil of intestine. 



A simpler form of apparatus is shown if in fig. 147, where a glass 

 plate A has attached to it two pieces of wax C C, which support and 



* Kanvier's ' Traite technique d'Histologie,' 1878, pp. 603-5 (2 figs.), 

 t Of. Dr. E. Klein in ' Handbook for the Physiological Laboratory,' 1873, 

 pp. 108-9 a fig.). 



X Thauhnffer, L., 'Das Mikroskop,' 1880, p. 152 (1 fig.). 

 Ser. 2.— Vol. III. 3 B 



