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motce. 



DR. A. Rothpletz {Botanisches Centralblatt, 1892, pages 

 265 — 68) advances an interesting theory as to the for- 

 mation of oolite. An examination of calcareous material 

 from the shore of the Great Salt Lake, Utah, U.S.A., revealed the 

 fact that they were covered with a bluish-green coating, which con- 

 sisted of colonies of the lime-secreting algae, Glceocapsa and 

 Gloeotheca. The lime enclosed by the alga is in roundish masses 

 and is of a finely granular texture. Dr. Rothpletz says they are 

 undoubtedly produced by these algse. He has also investigated 

 the oolitic bodies from the shores of the Red Sea, and believes 

 that they are produced by similar algae. Analogous structures are 

 described from the limestone of the Vilser Alps. The author is 

 of the opinion that the greater number of the marine calcareous 

 oolites with a regularly zoned and radial structures are produced 

 by these algse. 



Apropos of the Great Salt Lake, Dr. J. E. Talmage, in the 

 Microscope for December last, disposes of the assertion, often made, 

 that no living thing can exist in its waters. He records the pre- 

 sence of four forms : — i, Artemia fertilis, Verrill, abounding in 

 large numbers ; 2, Larvae of one of the Tipulidae, probably Chi- 

 ronomus oceaniciis (Packard) ; 3, A species of Lorixa, probably 

 C. decolar (Uhler); and lastly, the larvae and pupae of a fly, 

 Ephydra gracilis (Packard). He also considers that the "vege- 

 table life of the lake is a subject worthy of investigation." 



Hitherto the two groups of Macro- and Micro-lepidoptera into 

 which butterflies and moths have been divided have been charac- 

 terised by the former including all the large and conspicuous 

 species, and the latter only containing small and inconspicuous 

 moths. In a recent communication to the Entomological Society 

 of London, Dr. Chapman has endeavoured to raise the Micros in 

 general favour by transferring to that group several of our finest 

 moths. According to him, the pupa of the Goat-Moth {Cossus 

 ligniperda) possesses all the characteristics of a typical micro-lepi- 

 dopterous pupa, and for a similar reason the genera Sesia^ Zygcena^ 

 Frocris, and Hepialus ought to be placed among the micros. The 

 loss of the pretty burnets, clearwings, and foresters will hardly be 

 welcome news to the macro-lepidopterist, nor will the disturbance 

 of a well-arranged drawer of micros, to make room for the large 

 and chronically " greasy " goat and swift moths, be considered an 

 altogether favourable change. Still, other elements besides the 



