INSECTS OF THE PACIFIC 

 COAST 



BY VERNON L. KELLOGG 



Professor of Entomology, Stanford University 



WHEN one speaks of the insects of the Pacific, 

 they are the insects of Pacific shores and 

 Pacific Islands that one refers to. For with 

 all the amazing adaptiveness of insects to variety of 

 hahitat and hahit, and with all the pressure of 

 enormous numbers of species and individuals to 

 drive them far and farther and into all the available 

 places of earth, the insects have, curiously, so far 

 not invaded the oceans. Although they constitute 

 of known living animal kinds a full two-thirds, per- 

 haps three-fourths, they are restricted in habit to 

 but one-third part of the earth's surface, to-wit, its 

 dry land and fresh and brackish waters. The real 

 salt sea is tenantless of insects. A few long-legged 

 surface-treading kinds are found on ocean waters 

 far from land, but these are really inhabitants of 

 surface sea-weed patches, which, like their fresh- 

 water cousins, the familiar water-striders or skaters 

 of ponds and quiet stream-pools, can run or glide 

 quickly over the water's surface, denting but not 

 breaking the supporting surface film. 



There are also a few small kinds which haunt 

 the beaches and rocks between tide lines for sake of 

 the rich harvest of food thrown up by the waves. 

 Such a kind is a little long-legged fly with atrophied 

 wings, which lives on the headlands of the Cali- 

 fornia shore in the Monterey Bay region. When the 

 tide is out it runs actively about, looking like a small 

 slender-bodied spider, over the rough damp rocks, 

 seeking bits of organic matter thrown up by the 

 waves that dash over the rocks at high tide. When 

 the waters come back these odd little flies seek 

 refuge under small silken nets they have spun across 

 shallow depressions in the rocks. They cling des- 

 perately to the under side of the protecting silken 

 mesh, while the great waves dash and break over 

 them. Of course they are much of the time actually 

 submerged in salt water. But they stand it. 



Recently a similar and closely-allied fly has been 

 found on the shores of bleak South Georgia Island 

 in the South Atlantic about 500 miles east of Pata- 

 gonia. And another tide rock fly of like habits is 

 known from the cold and tempestuous Kerguelen 

 Island of the South Indian Ocean. 



141 



