144 



THE INFLUENCE OF INANIMATE SURROUNDINGS, 



migratory fish the salmon, the eels, many herrings, p'aice, and 

 others. More interesting, because less generally known, are 

 the cases of marine Insects or insect larvse. Slabber has de- 

 scribed the larva of a fly which lives in the sea, and I myself 

 frequently met with a similar one in the Philippine and China 

 seas ; Auclouin studied the habits of a beetle (Blemus flavescens) 

 which lives in the sea like the fresh-water spider, Argyroneta, 

 aquatica ; Packard has given a list of the insects which occur in 

 the salt waters of North America, and he enumerates as be- 

 longing to them not less than ten different species of beetles, 

 flies, and bugs. In the Pacific Ocean and Philippine Sea, I have 

 myself .often found various Insects and even Spiders in the sea, 



FIG. 36. Halobates sp., caught by me far from land in the China Sea. 



sometimes swimming in great numbers on the surface, some- 

 times creeping between rocks under water by the shore. A bug 

 of the genus Halobates (fig. 35) is particularly common iti these 

 seas, besides the above-mentioned larvse of flies. This genus was 

 discovered by Eschscholtz, and now includes fourteen species 

 living in seas the most remote from each other. The species in 

 question runs about like our "Water-Bug, Hydrometra, in great 

 numbers and in every stage of development, on the high seas 

 hundreds of miles from land. Among Mollusca a species of 

 Unio lives in the Brisbane River within reach of the flood-tide. 

 Dr. Carpenter found Planorbis glaber (Jeffreys) at a depth of 

 1,415 fathoms at Cape Teneriffe. Neritinaviridis, in the West 



