1892.] MICROSCOriCAL JOURNAL. 215 



doxa, O. F. M., is the species. I cannot as yet prove the spe- 

 cific change from //oma'oc/ad/a filifor7)iis to Bacillaria para- 

 (/o.va, but they are both common in the Passaic river at Harrison, 

 N. J., and evidently, when viewed carefully, are seen to be the 

 same. The size of the frustule is large and small ; they are both 

 the same shape, and the only diHerence between them is that one 

 {^H. Jiliforniis') is in a frond or tube, and the other {B. para- 

 doxa) is free and moving, but also commonly still. In fact, as 

 W. Smith says, "■ the frustules of Bacillaria are those of a 

 NitzcJiiay It seems to be a form of the species that is for the 

 distribution of the species in place, for Homceocladia Jiliforiiiis 

 is fixed by reason of the frond, and Bacillai-ia can only be the mo- 

 tile form, and can travel up the stream into fresh water where the 

 water is stiller than in the ocean. Or it may be the motile form 

 (^Bacillaria) can travel down the stream best and becomes fixed 

 {Ho/nceocladia) in the ocean. In fact this brings up the point of 

 determining the origin of Diatofuaceic generally. Were they 

 created in the ocean or in fresh water.'' I believe they were 

 created in fresh water. For when they were formed there was 

 no salt water. The rain that fell was of course fresh water, and 

 lakes and sea were formed of fresh water. Then after a time, or 

 immediately, salt (sodium chloride) was formed from the hydro- 

 gen chloride (Hydrochloric acid) and- sodium carbonate, or some 

 other salt of sodium, present on the earth, and thus the sea be- 

 came salt. The ocean that formed in Utah and Colorado was 

 Eocene and fresh water, and I have called it the Occidental Sea. 

 (Vide my paper on the Diatoms of the Pacific States in the 

 American Journal of Science for November, 1S91.) But this 

 carries us into the geology of the Diatoinacecc^ which I do not 

 mean to go into at the present time. Nor yet the origin of the 

 Diato7nacece themselves, whether they are vegetable or animal, 

 or Protista or what. But I will say that if they can be 

 classed anywhere I am of the opinion that they must be 

 classed as Protista at present, viz., organisms that exist 

 as free beings, without differentiation from vegetables 

 or animals; that do not have a stomach, that breathe 

 carbon dioxide, and reproduce by the vmion of spermatozoids 

 (or male organs) with female organs. But this brings us again 

 to a difiicult subject to treat of, the genesis physiologically of the 

 Diatomaccce. I do not desire either to go into this, but I have 

 for years been investigating their physiology and think I have 

 cleared up the way, until some patches of dawn at length are 

 seen. 



But the species and genus of the forms we have been treating 

 of is about this genus, Sigmatella^ F. T. K., 1833, and species 

 paradoxa^ O. F. M., 17S8. I very much doubt if this species is 

 not the same that has been called Syiiedra (^JVitzschia) sigmoidea 

 or Bacillaria sigmoidea^ D. C. L. N., 1817. Having now 

 cleared up the genus Sigmatella {JVitzschia or Synedra) , we 



