188 The Ottawa Naturalist. [January 



NOTES ON EXPERIMENTS RELATING TO THE ORIGIN 



OF LIFE-FORMS. 



By Mark G. McElhinney. 



On January 17th, 1908, while examining se^eral sHdes, 

 made on May 6th, 1906, I made an interesting find. 



Near the centre of slide No. 3 was an object, very different 

 from the surrounding crystals. It closely resembled a small star 

 fish, having six radiating arms. Five of these were slightly 

 wavy, while the sixth had a decided curve to its outer third. 

 It lacked the rigid geometrical form and outlines of the usual 

 crystals, and the arms appeared to be rounded in section. 



After it had been examined by myself, my assistant and 

 several members of my family, I lost it on the field. After 

 some minutes of searching it was found and then again lost. 

 Being called away I did not look for it again for several hours 

 and was disappointed in not rediscovering it. Some two hours 

 of further search failed to again reveal it, and, as the slides 

 change somewhat rapidly when removed from the incubator, 

 I concluded that further search would be useless. 



It was identical in form with a diatom described by Carpen- 

 ter as Bacteriastrum jurcatum which is frequently found in the 

 stomachs of Ascidians, Salpae, Holothuriae and other marine 

 animals. 



My highest power being a quarter inch, I w^as unable to 

 examine its structure and so am unable to say whether it was the 

 true diatom or a crystal prototype. Its disappearance would 

 incline one to the latter view. There not being time to stain and 

 cover it, it may have become detached from the slide. Generally 

 when crystals become detached, an outline remains on the slide; 

 in this case I could find no outline. 



Near it was a large crystal bv which I tried to locate it. 

 After the disappearance of the starlike form I saw an object 

 which before had been unnoted; it resembled a large irregular 

 amoeba, but I cannot say that it was not there before. 



All of the slides are covered by an open network of fine 

 lines which branch out irregularlv, like rivers and their tributaries 

 on a map. They appear to be a primitive form of vegetable life. 



The slides were made by evaporating drops of a three per- 

 cent, solution of sodium chloride, containing certain proportions 

 of the elements found in animal life, and to which were added 

 bisulphide of carbon and .silicic acid. 



On the morning of the 18th, I found, on the same slide, 

 a form resembling a ciliated columnar cell. No movement was 

 detected in either form. When my photographic apparatus 

 is completed, I hope to be able to make positive records of the 

 slides. 



