434 NOTES. 



true spiders in fissures in blocks of coral which were under water at 

 every high tide ; they were very common in Bohol and at Zamboanga 

 in the Philippines, but as yet remain undesoribed, for my collection of 

 Araohnida is in the Hamburg Museum, and has not been worked 

 upon. 



3. Insecta. — Darwin, in his well-known Naturalist's Voyage, alludes 

 in many places to marine insects, principally beetles and bugs. Many 

 insects have lately been discovered on the coast of North America by 

 Baird (i2ep. on the Condition of the Sea-fisheries of tJw South Coast of Nem 

 England, 1 871-2, p. 1) and Packard {Proc. Essex last. vol. vii. p. 44, and 

 SlUiman's Journal, WTij'p.VAl). These are beetles, bugs, and flies. I 

 found a few marine insects in the Philippine seas, but they unfor- 

 tunately remain undesoribed. Of older observations I may mention 

 Slabber's dipterous larva, probably the larva of a species of Chironomus ; 

 and I found an abundance of a very similar species in the Philippine 

 seas, where swarms of flies sometimes cover the surface in still bays ; 

 then Audouin, who observes that JSlemiis fnlrescens surrounds itself, 

 like the fresh-water Argyroneta, with a bubble of air. Among the 

 Hemiptera — Salda, Corixa, Hygratreehvs, and Halolafes — the species of 

 Halobates are most conspicuous, for they are found in every stage of 

 development running about on the surface of the sea, often hundreds 

 of miles from land. Eight species of the genus, as I am informed by 

 my friend Dr. Hagen, have been described ; that described in the text 

 and discovered by me is a new species and the largest of all. They are 

 found in the Atlantic, Indian, and Pacific Oceans, as well as in the 

 Chinese Sea, but only in tropical or subtropical regions. 



Insects are also found in salt-water lakes inland. Packard found 

 eight different species in Clear Lake (^Sillinmn's Jim/mal, 1871) and one in 

 Late Mono. Numerous insects exist in the brine lakes of Europe, but 

 no collection or complete description of them is known to me. I experi- 

 mented this year on some larvas of flies which I found in a basin in the 

 courtyard of the Wiirzburg University ; they lived in sea-water very 

 happily for five or six days, but then perished. I suspect, however— and 

 shall test it more accurately next year — that they died for want of food. 

 Compare with this Plateau's experiment ; see below. 



MoUvsca. — Cyclas, Cwio, and Anodonta live in the Livonian Gulf 

 associated with Tellina and Vcn-w. _ In the Baltic we find Zymntna 

 aii/riculoHa and ovata, and Neiitinafluviatilis with marine moUusca. 



Paludiiia and Nentina are found in the Caspian with Mytilus and 

 Cardium, according to Eichwald. 



Planorbis glaier (Jefl'reys) is found in 1,415 fa'homs north of Cape 

 Tenez, Algiers. 



Uttio sp., vrithin reach of the salt-water flow in Brisbane river; 

 CVoy. of Rattlesnalie, vol. ii. p. .S62). Baer found Unio at the mouth of 

 the Dwina. 



