126 JOURNAL OF THE [November, 



the objective could be plunged down into any fluid without in- 

 juring it, and would always be correct for a ten-inch tube with- 

 out adjustment. 



In using an oil-immersion lens with the cover-cap, a drop of 

 oil is placed on the inside of the cover-glass, and the lens can 

 be used in urine, blood, or other liquids. 



The oil can be allowed to remain there if the lens is perfectly 

 tight, saving time and trouble in repeated examinations of this 

 kind. The cap also serves as a protection to the lens. It can 

 be easily removed and cleansed at any time, and the cover-glass 

 can be replaced if broken. 



Mr. DeWitt said that he had used the objective and fitting 

 exhibited by Mr. Wales, in the examination of pond-life in small 

 aquaria, by plunging it down into the water as suggested by Mr. 

 Wales, and had found it useful and convenient, in that it made 

 possible the repeated examination of certain forms like Vorticella, 

 Lacinularia, etc., without removal to the slide or live-box and 

 without injury to the objective. 



GIZZARD OF THE CRICKET. 



Mr. Hyatt : " The gizzard of the cricket differs from that of 

 the chicken in that the chicken swallows its food whole, or in 

 large pieces, passing it first into the crop and from there into 

 the gizzard, which is a powerful muscular organ. This is always 

 stored with small gravel or rough stones, which, being com- 

 pressed by the contraction of the muscular bands, grind up the 

 food, which afterwards passes into the stomach. But the gizzard 

 of the cricket is lined with very curious teeth, and does not con- 

 tain gravel or pieces of stone. The food when swallowed is 

 passed along to the crop in the same manner as in the chicken. 

 There is first a small expansion, then follows another, which we 

 may call the gizzard, and from that the food passes to the 

 stomach. In this gizzard are bands running down from one 

 side to the other, the space between being set with very curiously 

 shaped teeth, which are pointed toward the centre. The com- 

 pression of the muscular fibres of the gizzard upon these teeth 

 grinds up the food." 



