FERRIS: MINUTE INSECTS 517 



ber of species, and total number of specimens, the United States National Mu- 

 seum has much the best representation, though the Silvestri material at Portici 

 is significant, and that recently studied b.y Delamare is important. Valuable 

 recent material also belongs to the Bernice P. Bishop Museum, Chicago Natural 

 History Museum, and the California Academy of Sciences, owing mainly to the 

 field work of E. C. Zimmerman, Henry S. Dybas, and E. S. Ross, respectively. 



Silvestri 's work included detailed descriptions and sketches of setal patterns, 

 but it is sometimes difficult to recognize critical specific differences from his 

 papers. Caudell was the first to describe winged individuals. His descriptions 

 are brief and clear. Gurney developed the significance of concealed male geni- 

 talia, stressed the preservation of most material in alcohol, and brought out the 

 first comprehensive review (Proc. Ent. Soc. Washington, 40:57-87, 1938). 



Zoraptera are widely distributed in the tropical and warm temperate areas 

 of both hemispheres, including many small islands far from continents, but are 

 not recorded from the mainlands of Australia, Asia, and Europe. They were 

 first thought to be inquilinous with termites, but that frequent association is now 

 known to be correlated with preferences for similar environments rather than 

 a close social relationship. Cramp ton was much impressed by the apparent phy- 

 logenetic relationship to psocids (Corrodentia), and Delamare 's recent contribu- 

 tions on external sclerites and weakly defined castes indicate close relationship 

 to termites. Information on biology has gradually grown, owing mainly to the 

 observations of T. E. Snyder, H. S. Barber, and other associates of Caudell, to 

 Gurney's notes, and to recent studies by Delamare. Zoraptera are not known 

 to be of any economic importance. 



We may expect the steady growth of knowledge about species and their dis- 

 tribution. Possibly other genera will be found. Diligence and knowledge of how 

 to look for and recognize Zoraptera are rather essential to effective collecting. 

 Detailed biological work is needed, and a comprehensive study of the mor- 

 phology in comparison to that of termites and widely separated families of 

 psocids may be quite revealing as regards phylogeny. A student on such a prob- 

 lem should be advised by someone acquainted with psocid classification, so that 

 obscure psocid groups may be consulted. 



SOME MINUTE INSECTS: ANOPLURA, MALLOPHAGA 

 AND THE SCALE INSECTS 



G. F. Ferris 

 Stanford University 



Gorgeously colored butterflies and glittering beetles were for long the pri- 

 mary objects of interest to entomologists, with the flies and bees and wasps in 

 a somewhat secondary place. All of these insects fulfilled the common desire of 

 collectors to possess objects of beauty and curiosity which could be displayed 

 to admiring onlookers. This circumstance, in addition to the fact that minute 



