[43] COLLECTING AND PEESEEVING INSECTS ETLEY. 



On tlie other hand, our knowledge of the earlier states of Coleoptera 

 is yet very imperfect as compared with the LejDidoptera. Coleopterous 

 larvae are, with few exceptions (notably Ooccinellidse and some Chrys- 

 omelidse), much more difficult to find and rear, and their distinguishing- 

 characters are more difficult to study. The few comprehensive works 

 on Coleopterous larvse that have been published are based on rather 

 scant material and none of them deal with the l!^orth American fauna. 



Coleoptera occur in all climates and in all locahties. Species are 

 known from the highest northern latitudes ever reached by man, and in 

 the tropics they occur in an embarrassing richness of forms. They are 

 found in the most arid desert lands, in the depths of our subterranean 

 caves, and on our highest mountains up to the line of eternal snow. 

 The open ocean and the open water of our 

 Great Lakes are the only regions free from 

 them. As a rule, the number of species gradu- 

 ally increases from the Arctic regions toward 

 the tropics, but it would be difficult to decide, 

 speaking of North America, whether or not the 

 fauna of the Middle States is poorer in the 

 number of species than that of the Southern 

 States 5 or whether the beetles of the Atlantic 

 slope outnumber those of the Pacific States « & 



or those of the Central region. On the Pacific ^'°- ''vf Ground-beetle iCaio- 



^ soma caliaum) . o, larva; 6, adult. 



slope the influence of the seasons on insect life 



is greater than on the Atlantic slope. While in the latter region a num- 

 ber of species may be found the whole year round, there is, in the more 

 arid regions of the West, an abundance of insect life during and shortly 

 after the rainy season, with great scarcity during the dry season, ex- 

 cept, perhaps, on the high mountains. 



Few persons have had a more extended experience in collecting 

 Coleoptera than Mr. E. A. Schwarz, one of my assistants, and the 

 following account has been prepared by him at my request and is given 

 in extenso. 



Winter Collecting. — There are more species of Coleoptera Mbernating in the 

 imago state* than in any other order and winter collecting is therefore most profit- 

 able in many respects. For instance, great swampy tracts which are inaccessible in 

 the summer season harbor an abundance of rare Coleoptera, which either can not 

 be found in summer time or are found at that season with the greatest difficulty. 

 At the approach of winter, however, all or most of these species will leave the swamp 

 and seek drier ground, where they hibernate under old leaves, under bark of trees, or 

 in rotten stumps near the edge of the swamp . Such places will, therefore, give a rich 

 harvest to the Coleopterist late in the fall, during warm spells in midwinter, and in 

 very early spring. If the temperature is below the freezing point, or if the ground is 

 frozen hard, no winter collecting should be attempted, first, on account of sanitary 



*There are a few species of Coleoptera known in Europe which belong to the true 

 ^' winter insects, " i. e. such as appear in the imago state only during winter time, 

 but whether or not we have such species in our own fauna has not yet been ascer- 

 tained. 



