Geological Society, o99 



Of these thirty species only two were determined as occurring 

 in Catch previously, namely Trigonia Smeei and T. ventricosa. The 

 former has long been known as an Indian species, and the latter 

 also in India as well as in the Uitenhage strata of South-east Africa, 

 and lately it has been found in German East Africa. 



In the Appendix at page 121 Dr. Kitchin refers to the Mesozoic 

 MoUusca collected during W. Bornhardt's Journey in German East 

 Africa (1895-97), and described by Dr. G. Midler in 1900, who 

 regards two of the species as Jurassic; but two of the others he 

 considers to be of Lower Neocoraian age, namely T. ventricosa, 

 Krauss, and its associate T. Biyschleiji, Miiller. T. Kuchni, Miiller, 

 is said to be of Upper jSTeocomian age. It is evidently certain that 

 there is a resemblance (Dr. Kitchin says) of the German East- 

 African fossils to those of the Oomia group and those of Uitenhage, 

 as far as the lamellibranchs bear evidence at present (pages 2, 115, 

 121, &c.). 



The numerous figures of TrigonicB in the ten lithographic plates 

 are excellently well drawn, of natural size, by Miss G. M. Wood- 

 ward, of London. 



Circulars on Ar/rindtural Economic Entomoloqy. 

 Issued by the Trustees, Indian Museum. 



We have received the following numbers of these useful publications, 

 which are accompanied with good recognizable uncoloured illustra- 

 tions, and are issued at the price of 3 or 4 annas per dozen, for 

 general circulation in India. 



No. 1. The Kice Sapper (Leptocorisa acuta). 



2. The Bengal Rice Hispa {Hispa cpnescens). 



3. The Sugar-cane Borer {Chilo simplex). 



4. The Rhinoceros or Date-Palm Beetle {Oryctes rhinoceros). 



5. The North-west or Migratory Locust {Acridium pere- 



grinum). 



6. The Cut- Worm (Agrotis ypsilon). 



PROCEEDINGS OF LEARNED SOCIETIES. 

 GEOLOGICAL SOCIETY. 



January 20th, 1904.— Sir Archibald Geikie, D.C.L., D.Sc, Sec.R.S., 

 Vice-President, in the Chair. 



The following communication was read : — 



' On the Jaws of Ptychodus from the Chalk.' By Arthur 

 Smith Woodward, LL.D., F.R.S , F.L.S., F.G.S. 



Hitherto no traces of the cartilaginous jaws of this fish have been 

 found in association with the d''ntition; but Mr. Henry Willett has 



