CHAP. II 



ILEMATOCOCCUS 



241 



when divided by 300. It has been found that such 

 organisms as H^matococcus travel at the rate of one foot 

 in from a quarter of an hour to an hour; or, to express 



VHj. 68. — A, I la-iiiatococcHs pluvialis, niolile phabc. Living bpecinien, hhuwin^ 

 protoplasm with chi"omatophore-> (chr) and pyrenoids iPyr)^ cell-wall {c. lu) 

 connected to cell-body by protoplasmic filaments, and flagella (_/?). The scalu 

 to the left applies to Figs. A — D. 



]!, resting stage of the same, showing nucleus {mi) with nucleolus {nu'), and thick 

 cell-wall (c. iv) in contact with the protoplasm. 



C, the same, showing division of the cell-body in the resting stage into four 

 daughter-cells. 



]J, the same, showing the development of flagella and detached cell-wall by the 

 daughter cells before their liberation from the enclosing mother-cell-wall. 



K, Ifa^matococcus lacKstris, showing nucleus («?/), single large pyrenoid {pyr), 

 and contractile vacuole (c. z'ac). 



V, diagram illustrating the movement of a flagellum ; a[\ its base ; c, c', c" . differ- 

 ent positions assumed by its apex, (From Parker's Biology : li, after LJiitschli.) 



the fact in another and fairer Ava)', that they travel a distance 

 equal to two and a half times their own diameter in one 

 second. In swimming the pointed end is always directed 



Pkact. Zuul. R 



