HOOKE 143 



gluten" has not been refuted, but confirmed, by the 

 modern microscope. 



Hooke remarks the " strength and agility of these 

 creatures (insects) compared to their bulk, being, pro- 

 portionable to their bulk, perhaps an hundred times 

 stronger than an horse or man." This way of stating 

 the case is founded upon a fallacy, which it seems 

 impossible to dispel, and Hooke's mistaken comparison 

 is still reproduced in popular books of natural history. 



Obs. 38. The wings of insects are here dealt with, 

 and the scales of a moth's wing well figured. 



Obs. 39. The plate shows the head of a " grey drone- 

 fly," ^ drawn on a large scale. Hooke tells us that 

 the corneal facets looked like holes, but that by 

 observing the reflections from their surfaces he was able 

 to correct the false impression. He shows that the 

 drone-fly has its compound eyes "bisected," to use the 

 modern term, the lower part being composed of lenses 

 distinctly smaller than those of the upper part.^ Each 

 of these "pearls or hemispheres" is, he doubts not, a 

 perfect eye. 



Obs. 42. A good figure of a " blue fly " is given. 



Obs. 43. The " water- insect or gnat" is described. 

 The larva and pupa figured are those of Culex, but the 

 fly is what he calls a " tufted or brush-horned gnat," i.e. 

 a Chironomus. Much additional information concern- 

 ing the early stages of these insects was afterwards 

 supplied by Swammerdam and R^.aumur. Hooke com- 

 pares the gnat-larva hanging by its tail from the 

 surface-film to an opossum which he had seen in London, 

 and which, he tells us, had been described by Piso in his 



^ The figure is so imperfect that the fly is not determinable. 



2 Sucli bisected eyes occur not only in some Diptera but in inseots of other 

 orders ; their special use is unknown. 



h 



