NOTES AND MEMORANDA. 457 



also figured the same Spirilhcm-iovm of Bactermm rulescens in 

 the ' Eevue des Sciences Naturelles^ torn v, 1877. I do not 

 feel satisfied from the account given by Ewart and Geddes that 

 the bodies which I have called '' loculi ^' and which they term 

 " spores^' have any characters which justify the use of the latter 

 term in regard to them. They do not appear to be the same 

 kind of bodies in origin as the so-called " spores " discovered by 

 Cohu in Bacillus, and it is not at all certain that they germinate, 

 as Ewart and Geddes have inferred, though their observations lend 

 a certain amount of probability to that suggestion. 



In a second paper in the same journal Dr. Ewart discusses the 

 ' Life-history of Bacterium termo and Micrococcus.' According 

 to his observations Bacterium termo elongates under certain con- 

 ditions into small filaments in which micrococcus-like bodies 

 {" spores '') are formed as in Bacillus antliracis. At the same 

 time Ewart is inclined from certain experiments to hold that 

 besides the micrococcus-like spores of Bacteria there are inde- 

 pendent micrococci which do not give rise to Bacteria. Inter- 

 esting notes on conditions affecting the life of Bacteria are also 

 recorded. 



Mr. Dallinger, who with Dr. Drysdale was the first to discover 

 (Sept. 1875) the flagella (one at each end) of Bacteriim termo, 

 has recently measured the thickness of these filaments. He finds 

 it to be a little less than the -roo-j-ro-o^h of an inch. 



Messrs Dallinger and Drysdale are, I believe, the only ob- 

 servers who have succeeded in seeing the flagella of Bacterium 

 termo. They have done so by the use of the best objectives and 

 the most carefully contrived methods of illumination which the 

 microscopists of this country have devised. Other naturalists 

 had inferred the presence of such flagella, and Cohu had seen 

 and drawn them in the case of the large Sjoirillum volutans. 

 The larger Bacteria (such as the large forms of B. rulescens 

 erroneously assigned to the genus Monas with which they have 

 no relation, under the names Monas OJceni, Monas vinosa, Rhahdo- 

 monas rosea), possessing thicker flagella, were studied, and their 

 flagella recognised after the Enghsh observers had made their 

 discovery on the much more difficult object, B. termo. In the 

 journal of the Royal Microscopical Society for September, 1878 

 (vol. i. No. 4), Mr. Dallinger gives large figures drawn to scale, 

 and showing the flagella of Bacterium termo, B. lineola, Bacillus 

 subtilis, B. ^ilna, Vibrio rvgala. Spirillum imdula, and Spirillum 

 volutans. 



E. Eay Lankester. 



The Development of Calcareous Sponges. — Professor Franz 

 Eilhard Schulze returns to this subject in the 'Zeitsch. wiss. Zool,, 



