INSECTS. TEST-OBJECTS. 307 



caterpillars of some of them bury themselves in the article on which 

 they feed, instead of making the silken tube spoken of. The moths 

 also differ very much in appearance : the commonest kind is of a light 

 buff; one species, Tinea Tapetzella, fig. 138, is nearly black, with the 

 tips of its larger wings white, or pale grey. 



Mr. Topping, the careful preparer of microscopic 

 objects, generally furnishes three kinds of test-objects, 

 which he covers with the thinnest glass, in order that 

 object-glasses of the highest powers may be used in fi 138 

 the examination of them. The following are arranged The Black Clothes- 

 according to their difficulty as test- objects : moth. 



Fos. N. gracilis. 

 Amician test. 

 Grammatophora. 

 Ceretonis faschiota.. 

 Navicula cuspidata. 



angulata. 



strigosa. 



lineata. 



Spencerii. 



N. baltica. HAIRS, 



hippocampus. 



strigitate. 



formosum. 



SCALES. 



Meadow Brown. 

 Pontia Brassica. 

 Azure Blue. 

 From Gnat's Wing. 

 Tinea Vestianella. 

 Amathusia Horsefieldiii 

 Morpho Menelaus. 

 Podura plumbea. 

 Lepisma saccharina. 



Indian Bat. 

 )r Mouse. 

 Mole. 



Larva of Dermistes. 



Mr. J. T. Norman, preparer of specimens for the microscope, 10 Fountain Place, 

 City Koad, furnished the author with a similar list for publication. 



The caterpillar's foot is made up of a series of booklets, which 

 enable him to cling with ease to the surface of a leaf or stalk of a plant. 

 A magnified view of one is given at No. 5, Plate IX. 



The Homoptera form three great groups or tribes. The first, the 

 Cocdna, is composed of numerous minute insects, of which the history 

 is still very imperfectly known. Of these the tarsi have only one joint. 

 The males are furnished with two wings, with a few straight nervures ; 

 they are destitute of a rostrum, and pass their pupa stage in a state of 

 repose. The females are destitute of wings, possess a rostrum, and 

 appear to undergo no metamorphosis whatever. These curious little 

 creatures, whose history is so singular that some authors have pro- 

 posed the formation of a separate order for their reception, are princi- 

 pally inhabitants of the warmer regions of the earth, although many 

 species are found in our own country, where some of them are well 



