APPENDIX. 127 



that there is one extended deposit covering a great extent of country. In fact tlie Japan specimens 

 resemble those from California in a very marked degree, and much more so than the Virginian ones, 

 containing almost identically the same species of Diatomaceas that I have found therein. I am not, at 

 present, prepared to give a list of those species, but the following genera have been identified, all of 

 which, with the exception of the last, are exclusively marine, but the species of that last genus C'occo- 

 neis, found in this deposit, are decidedly of marine origin also. 



Arachnoidiscus. Creswellia. 



Auliscus. Dictyocha. 



Asterolampra. Isthmia. 



Actinoptychus. Gephyria. 



Aulacodiscus. Grammatojjhora. 



Stictodiscus. Rhahdonema. 



Goscinodiscus. Biddulphia. 



Triceratium. Cocconeis. 



Doubtless species belonging to other genera will be detected hereafter, when I study these speci- 

 mens more attentively, when it is my intention to make out a full list of the species I may find and 

 publish it, with descriptions and figures of such as I consider new or undescribed, through the 

 medium of some one of our scientific societies. Meantime I send you herewith a couple of slides of 

 this material, mounted in such a manner that you can judge for yourself of its richness in microscopic 

 forms and their beauty, and in many cases, identity with those found in the Californian stratum, a 

 slide of which accompanies them. 



No. 1. " Terrace dejMsil {loam) from the valley north of the mountains of Sinpaumjan." 

 Contains little but sand with a very few of the green colored crystals above mentioned interspersed 

 through it. 



No. 8. "Terrace deposit {loam) from Siwan, N. Chihli, China." 



This contains nothing of interest or by means ot which its origin can be traced, 



No. 10. "Gobi Sandstone, steppe deposit, Dec. 2, 1864." 



Consists entirely of clean coarse sandy particles, semi-crystalline in character, and with, or in which 

 the microscope reveals, no traces of organic remains. 



No. 11. " From the beds of volcanic ashes at Isoya, west coast of Yesso, Japan." 

 This specimen was examined in a superficial manner at first, but, besides consisting for the most 

 part of pinkish particles of minute size whose origin could hardly be guessed at, was deemed of very 

 little interest. A closer and more thorough examination, however, with higher power glasses revealed 

 decided traces of organic remains and those of an entirely unlooked for character, that is to say, there 

 were found in it, although only in extremely small numbers, straight sponge spiculae as well as globular, 

 so-called, " gemmules" from sponges, and at the same time dotted ducts from the woody portion of 

 some exogenous plant. Besides these, strange to say, I found fragments of the siliceous* epidermis 

 of three or perhaps four species of Diatomacese, decidedly aquatic plants and, in this case, all marine 

 in their habit. The genera represented in these very rare and minute fragments were Arachnoidiscus, 

 Cyclotella, Isthmia, and probably Goscinodiscus. Besides these the green colored crystals mentioned 

 above, as having been detected ia several of the earths examined, were seen in this specimen showmg 

 that there exists some connection between these various specimens in their origin. 



No. 12. "Alkaline sand from the shore of Lake Kirnoor, Mongolia." 

 No. 13. "Sand deposited in the valleys around Lake Bilikanoor, Gobi desert." 

 In neither of these specimens could I find the slightest traces of the remains of organized beings 

 or anything else by means of which I could judge of their origin. Thus, although the results of my 

 examination, conducted in the most careful manner, are in most cases but negative, yet, even there- 

 fore they are of interest, and you will be better able to judge than I am of their value. The dis- 



