42 GUIDE TO INSECTS. 



Table- Drawings and specimens of Trichodectes latm (1501, fig. 42) 



found on dogs, Menopon pallidum found on fowls, and other species 

 are exhibited. 



Like most parasites they are difficult to locate satisfactorily in 



Fig. 42. 



Trichodectes latus, from dog ; enlarged thirty-six times. 



any natural system, but they appear to be most nearly allied to the 

 Orthoptera. 



Order LEPIDOPTERA. 



On the west side of the gallery are cabinets of British Lepidoptera. 

 Four contain the collection of caterpillars prepared and presented 

 by the Rt. Hon. Lord Walsingham. Another contains the collec- 

 tion formed by the late William Buckler, the author of " The Larvae 

 of the British Butterflies and Moths," published by the Ray Society. 

 It was presented to the Museum by Robert Newbury, Esq. 



The foreign Lepidoptera are in cabinets on the East side of the 

 gallery. 



The insects of this Order are popularly known as Butterflies and 

 Moths. 



They undergo a complete metamorphosis. The larva is popularly 

 called a caterpillar; the pupa a chrysalis. The perfect insect has 

 the head free. The thorax is compact ; the prothorax very small ; 

 the mesothorax very large. The wings are very variable, clothed 

 (as well as the body) with scales. The mouth parts (Fig. 43) are 



