98 NEUROPTERA. 



are beautifully silvery. Isotoma Saltans, Agassiz, is a small black 

 species, which abounds on the glaciers of the Alps. 



Two species of Poduridce are likewise worth mentioning for 

 their habits. One is Achorutes DuUus, Tempi., found by Templeton 

 and Lubbock on the surface of standing water, and on sand-banks ; 

 and the other is Lipum Stillicidii, Schiodte, which frequents caves. 

 The former species is blue-black, and the latter white, and these 

 colours predominate in the family. 



The Anouridce are a small family resembling woodlice in 

 form. One species, Anoura Rosce, Gerv., found in the Jardin des 

 Plantes, is entirely of a rose colour. 



The eyes of several of the Thysanum and Collembola are different 

 from those of all other adult forms included with the insects. In 

 the Collembola they consist of from one to eight ocelli, arranged in 

 a series on each side of the head, thus offering an analogy with 

 those of Lepidopterous larvae. On the other hand, most of the 

 Thysanum have two compound eyes; and one or two genera have 

 been asserted by Mcolet to have ocelli similar to those of the 

 Collembola on each side of the head, a statement which Lubbock 

 has been unable to confirm. Several genera of both groups are 

 believed to be entirely destitute of eyes. 



NEUROPTERA PLANIPENNIA. 



Head of moderate size; antennae many-jointed, variable in 

 length, and sometimes very long, filiform, or clubbed ; wings naked, 

 generally of equal length; hind wings sometimes with long append- 

 ages ; metamorphosis complete ; pupa inactive. 



A very large and important group, rivalling the Odonata in'size 

 and beauty, and far surpassing them both in number and in the 

 singularity of their forms. They are, however, very poorly repre- 

 sented in Britain, and although we have representatives of several 

 of the principal genera, nearly all the larger and more conspicuous 

 species met with on the Continent of Europe are absent. They 

 are divided into three families, of which the second is by far the 

 most important. 



FAMILY I. Sialidce. 



Wings large, reticulated, deflexed, more or less projecting at 

 the anal angle ; antennae long ; body short and thick. 



