EVENINGS AT THE MICROSCOPE. 



are of the same sex ; we never see a Brachionus with male 

 and female eggs at the same time. What is very strange, 

 is, that the male has no shell, no spines, no mouth, no 

 jaws, no stomach, no intestines ; no ciliary wheels ; its 

 cilia, which are very long and powerful, being arranged in 

 one circle round the whole front. Its movements are ex- 

 ceedingly fleet. 



Perhaps you are tired of Brachionus, and are ready to 

 cry out, " Ohe ! jam satis ! " * Well, then, I will turn 

 him off, and show you another elegant little creature, the 

 Whiptail (Mastigocerca carinata). I have here in a bottle 

 some stalks of the Water-Horsetail (Chara vulgaris), which 

 I obtained from a pond a few weeks ago. These I examine 

 in this way. Taking hold of the Chara with a pair of 

 pliers, I pull it partially out of the water, and allowing it 

 to rest on the neck of the bottle, I cut off with a pair of 

 scissors, or with a penknife on my nail, about one-fourth 

 of an inch of the tips of three or four leaves, which adhere 

 together by their wetness. These tips I place in the live- 

 box, with a drop of water, and having separated them with 

 a needle, I put on the cover, and examine them with a 

 triple pocket lens ; holding up the box perpendicularly, 

 not opposite the light, but obliquely, so that the field is 

 dark ; but the light reflected and refracted by the ani- 

 malcules shows them out beautifully white and distinct, 

 even the minute ones. The forms and some characters of 

 the middling and larger can be quite discerned thus ; for 

 example, the slender tail of the one I am now going to 

 show you, I can thus see. The position of any particular 

 individual to be examined being thus marked, it is readily 

 put under the object-glass of the microscope. I have found 

 these leaves very productive of the more stationary ani- 

 malcules, the Rotifer a especially. 



It was in this way I this morning found the pretty and 

 delicate little Whiptail, which I am going to make the 



* " dear ! quite enough of this ! " 



