LIVING SPIROCHAETES 23 



the limbs of which intertwine. Thèse might be mistaken 

 for cases of longitudinal division were the évidence of stained 

 préparations only regarded. 



8° The movements of 8. halhianii and S. anodontae hâve been 

 compared with those of a large Spirochaete that I found in 

 Mytilus and with those of a smaller one occiiring in Sphaeriim, ; 

 also with those of the Spirochaetes of Tapes (Fantham). 

 There is great resemblance in ail of them. The Spirochaete in 

 Mytilus, previously unrecorded, is a large one, that of Sphae- 

 rium, wliich is also new, is a smaller form. 



90 Multiplication by both longitudinal and transverse divi- 

 sion occurs, and both processes hâve been followed completely 

 in living spécimens. I hâve also followed both processes in 

 S. recurrentis and S. duttoni and they are similar to what is 

 seen in S. balhianii and S. anodontae. 



100 In longitudinal division waves pass rapidly down the 

 body of the Spirochaete and a spht commences at one end. The 

 split continues and the waves passing down each daughter form 

 vibrate in unison. The daughter forms gradually diverge and 

 finally separate when there is an angle of 180° between them. 

 Ail entanglement forms hâve been eliminated from the obser- 

 vations of division and there is no doubt that true longitudi- 

 nal division occurs. 



1 P Transverse division is initiated by waves setting in from 

 the ends of the organism towards the centre. The waves meet 

 and die out, and return waves pass outwardsto the extremities. 

 Thèse processes are repeated many times, and after several very 

 rapid sets of waves in succession, the centre which has gradually 

 been getting thinner, parts in two, and two, free daughter 

 Spirochaetes are produced. Transverse division is aided by 

 reversais of the direction of the helicoid spirals of the bodies 

 of the daughter organisms, a right-handed hélix becoming a 

 left-handed one and vice- versa. 



120 Encystment of S. halhianii and S. anodontae has never 

 been seen, but organisms tightly coiled in the middle hâve 



