244 Geological Society, 



not true, at least for the time of year mentioned at the 

 beginning of these notes. All three of my visits to Esupua 

 were made during the iieaviest rains of the year, which, 

 according to native reports, do not seem to have the effect 

 which has been claimed for them in reducing the numbers of 



1 have elsewhere shown that Gl. palpalis Wellrnam is a 

 disseminator of human trypanosomiasis, and that this disease 

 is unfortunately on the increase in Benguelhi District. 



rilOCEEDINGS OF LEARNED SOCIETIES. 



GEOLOGICAL SOCIEXr. 



April 25th, 1906.— J. E. ilarr, Sc.D., F.Il.S., 

 Vice-President, in the Chair. 



The following communications were read : — 



1. ' Trilobites from Bolivia, collected by Dr. J. W. Evans in 

 1901-1902.' By Philip Lake, M.A., F.G.S. 



Several horizons are represented by these fossils. Tsvo speci- 

 mens of Peltura, probably from the Upper Linjula-Flags, were 

 collected at Cochaiya, about 3 miles north-east of Pata. Xew 

 species of Stfmj^^^'jsurus and Trlnudeus, probably of Arenig age, 

 were found about a mile from Apolo, Province of Caupolican. An 

 indeterminable species of Ojifjia was obtained from the right bank of 

 the River Caca, in the same province. Fluicops cf. arbuteits, Dal- 

 maaites Paitana, and D. Maecarna were collected in the track 

 from Apolo to San Jose de Chupiamouas, also in the province of 

 Caupolican. The nodules from which the}' were derived are 

 probably of Lower Devonian age. Descriptions are given of the 

 new species and other forms menlioned. It is worthy of remark 

 that, while the earlier forms show affinities with the contemporaneous 

 European fauna, the Devonian species are much more closely allied 

 to those of South Africa and North America. 



2. ' Graptolites from Bolivia, collected by Dr. J. W. Evans in 

 1901-1902.' By Ethel M. R. Wood, D.Sc. 



In black pyritic shales from three localities several specimens 

 of Diibimo(iraptus were collected : one referable to bijidiis, one of the 

 type of (iffiitis, and one of the Nicholsoai-type. Ph>iUo(jraptu8, 

 Glossogi'tqHns, Cri/pfor/ra/>tus, and Diplograptas were also obtaineK 

 A pale, silky grey shale shows also rare graptolites, belonging to a 

 species comparable with CVunacoiiraptus confertit.<. These forms 

 indicate that both the black and the pale shales belong to horizons 

 ill the Upper Arcnij; rocks (^ Lower Llanvirn of Hicks). 



