io8 



9. At all stages of the dissection make sure that 

 the glands are really present and that they have not 

 floated to the side or stuck to the needles. 



10. By this certain and rapid method, as many 

 as one hundred glands may be dissected out, put under 

 a coverglass, and examined microscopically in a day's 

 work. 



tttcf 



iu 



Fig. 43. The Salivary Glands of one side 



Method 2. Consists in isolating, by a series of 

 cuts, the anterior ventral portion of the thorax in 

 which the glands lie. 



1. Make a cut obliquely in an antero-posterior 

 direction, so as to sever the main mass of thoracic 

 muscle. 



2. Make a cut at right angles to this, passing 

 just behind the attachment of the first pair of legs. 



3. Cut through the neck. 



4. The glands lie in the portion thus isolated. 

 Considerable teasing out is still required to isolate 

 them from the surrounding tissues. Examine each 

 portion of tissue separated out, and remove to a fresh 

 clear drop of salt solution. 



Remember that in examining under the micro- 

 scope the apparent right hand is really the left, and 

 vice versa. 



