614- EXPLANATION OF THE PLATES. 



FIG. 



29. Plumiform gills in the mouth of the spiracles of the larva 

 of Cossus ligniperda. (Sprengel.) 



PLATE XXX. 



1 . Brain, spinal chord and .ganglions of a full-grown cater- 



pillar of Pontia Brassicte. a. The brain. I). The double 

 spinal chord, cd. Ganglions with a portion of their nerves. 



2. Brain, spinal chord and ganglions, after two days, when 



the chord is shortened. 



3. j ' when the animal is 



become a pupa. 



4. , 1 when it has been a 



pupa six days. 

 5. . just before it assumes 



the imago. 

 G. i - _ when it has become 



a butterfly. Voi,. IV. p. 24 . 

 7. Intestinal canal of the caterpillar, a. Saliva vessel, b. Silk 



reservoir, c. Gullet or oesophagus, d. Stomach, eee. Bile 



vessels. / Large intestine, g. Rectum. 

 8. ' " after it has assumed the 



pupa two days. 

 9. i after eight days. a. Crop 



or honey-stomach, first showing by the dilatation of the 



base of the oesophagus. 



10. . a. Honey-stomach be- 



come a lateral appendage of the oesophagus b. 



11. . of the butterfly, a. Honey-stomach. 



b. (Esophagus, c. Small intestine become very long. 

 d. Rectum. VOL. IV. p. 118. 



12. Anal portion of the interior of the female butterfly. 



a. Ovaries, b. Oviduct, c. Colleterium or varnish 

 secretor. d. Spermatheca or sperm receptacle, e. Part 

 of the spinal chord. /. Rectum, g. A secretory organ 

 filled with a thick white fluid, which is supposed to 

 lubricate the passage. VOL, IV. p. 132, 152. 



