338 Fossil Infusoria. 



19. P. semirufa. Ferruginea, antenna rum capitulus, capitis vertex, pro- 

 thoracis discus, elytra tota, protibiae omnino, metatibiarum apices, tarsique 

 undique nigri. Habitat Mexico. Corp. long. .425 unc. lat. .25 unc. 



20. P. Castor. Brunnea, prothoracis discus rugosus, brunneus, margini- 

 bus ochraceis : elytra sulcata, sulci profunde punctati : elytrorum humeri 

 nigri. Habitat Mexico. Corp. long. .28 unc. lat. .175 unc. 



21. P. Pollux. Nigro-amea: prothoracis marginibus, elytrisque totis 

 testaceis: pedes brunnei, tarsis piceis : elytra sulcata, sulcis profunde punc- 

 tatis. Habitat Mexico. Corp. long. .27 unc. lat. .16 unc. 



Mr. Newman also describes the following published spe- 

 cies. Rufipes and bipunctata of Fabricius ; biguttata of 

 Wiedemann; cyanea, minuta, cupricollis, virescens, margi- 

 nicollis, and nitida of Hope. Beryllina of Hope he consi- 

 ders a variety of cyanea ; and formosa and smaragdala, both 

 remarkable for their splendid colouring, he gives as varieties 

 of cupricollis. The number of distinct species is thirty, all 

 of them in the rich cabinet of Mr. Hope ; and also five named 

 varieties : one additional species is added from the British 

 Museum. 



Meetings of the Friends of Natural History, of Berlin. — 

 January 16th. Prof. Ehrenberg exhibited samples of the sili- 

 ceous earth, which was found a short time before, near Ebs- 

 dorf, in the neighbourhood of Liineburg, in Hanover. This 

 earth, which has been discovered at six different places in the 

 same district, forms two layers of different colours, and is co- 

 vered with one of peat-earth only, 1 J foot thick. The upper 

 stratum, which is from 10 to 18 feet thick, is very white, and 

 consists of pure silica, according to the analysis of Prof. Wig- 

 gers, of Gottingen. The second, the colour of which is brown- 

 ish grey, is at least 10 ft. thick; it also consists of silica, with 

 a small proportion of bitumen : the latter disappearing on 

 the earth being heated, its colour likewise becoming white. 

 As Prof. Hausmann of Gottingen suspected this earth to be 

 composed of the remains of organic beings, he sent samples 

 of both the varieties to Prof. Ehrenberg, who examined them 

 under the microscope. Both sorts are much alike, with refe- 

 rence to their composition, and not only contain the minute 

 shields of Infusoria, but consist of them. Prof. Ehrenberg 

 had distinguished in them sixteen different organic bodies, of 

 which fourteen are the siliceous tested of Infusoria. The white 

 or upper stratum is entirely composed of such testae, in a state 

 of perfect preservation, with a slight admixture of grains of 

 quartz ; much resembling in this respect the mountain meal, 

 (bergmehl), of Santafiora, but it is purer. Prof. Ehrenberg 

 has already distinguished twelve different species of Infuso- 

 ria. The brownish grey, or lower layer, consists of the same 

 testa, but in a less perfect state, and of two more species, 



