160 Miscellaneous. 



of the leg, appear of a dingy white, with a more or less extended black 

 marbling. 



Total length 0-058 m. ; length of the head 0"023 ; length of the 

 anterior extremity to the tip of the last ringer but one - 033 ; length 

 of the hinder extremity to the tip of the fourth toe 0*095. 



The single specimen of this species was discovered by Dr. Moritz 

 Wagner on the west side of the Andes in Ecuador, and is now in the 

 Zoological Museum of Munich. — Monatsber. der Akad. der Wiss. 

 zu Berlin, April 1862, p. 232. 



Discovery of Microscopic Organisms in the Siliceous Nodules of the 

 Palaeozoic Rocks of New York. 



At Prof. Dana's suggestion, Dr. M. C.White, well known for his 

 devotion to the microscope, has examined various specimens of the 

 hornstone nodules found in the Devonian and Silurian rocks of this 

 country, with a view to determine the presence of organisms analo- 

 gous to those well known to exist in the flints of the chalk. This 

 research has been rewarded by the discovery of abundant organisms 

 referable to the Desmidiese, besides a few Diatomaceae, numerous spi- 

 cula of sponges, and also fragments of the dental apparatus of Gaste- 

 ropods. Among the Desmids, there is a large variety of forms of 

 Xanthidia supposed to be the sporangia of Desmids, besides an oc- 

 casional duplicated Desmid ; also, lines of cells, some of which appear 

 to be sparingly branched. The researches have been mostly confined 

 to the hornstone of the corniferous limestone ; though extended also 

 to the hornstone from the Black-River limestone and that of the 

 sub-carboniferous limestone of Illinois, both of which contain some 

 organisms. 



The hornstone-nodules from the Black- River limestone (as well as 

 the corniferous) have been since examined also by Mr. F. H. Bradley 

 with similar results. 



These observations will be regarded with much interest by geolo- 

 gists as well as by microscopists. They carry back to a very early 

 epoch forms of life which have hitherto been looked upon as belong- 

 ing only to a much more recent era in the life of our planet. 



The analogy of these hornstone-nodules to the flints of the Chalk 

 is obvious ; and the discoveries here announced may be regarded as 

 establishing their similarity in origin. The organisms figured so 

 closely resemble those of the flint that they might be taken for them ; 

 it is difficult in all cases to make out a difference of species. 



The extreme abundance of the hornstone-nodules in our palaeozoic 

 limestones will render it easy to multiply observations in this new field 

 of research, which presents an interesting addition to the labours of 

 the microscopist. It will he remembered by those who undertake 

 such examinations that the use of turpentine renders the chips of 

 chert almost as transparent as glass. — Silliman's Journal, May 1862, 

 p. 385. 



