438 C. CLIFFOKD DOBELL. 



seen iu ordinary spirogyra forms (fig. 56). Some of these- 

 organisms are shown iu fig. 63, PI. 17. The nucleus is con- 

 siderably shorter than the cell, and always has the thickened^ 

 knotted appearance shown in the figures ; otherwise it 

 resembles the nucleus of typical spirogyra forms. 



(3) Bacilli of the spirogyra t3^pe from Mabuia 

 carinata. — In these lizards, captured in Colombo, I found 

 a large number of spirogyra forms in addition to the cocci 

 and flexilis forms already described. All the preparations 

 which I made of the contents of the large intestine were 

 fixed w'itli osmic acid and stained with Giemsa's or Leish- 

 man's stain. The following descriptions are therefore based 

 upon material so treated. 



The largest forms which I found (figs. 30-35, PI. 16) are of 

 considerable size. They reach a length of IQ in. They show^ 

 the organisation characteristic of spirogyra type organisms 

 with great distinctness. Forms with a nearly straight 

 nuclear filament (fig. 35), forms with a simple spiral or 

 zig-zag (fig. 34) and forms with a very much twisted filament 

 (fig. 31) were found. In fact all the modifications which are 

 seeu iu B. spirogyra itself were encountered. A modifica- 

 tion which I have observed comparatively rarely iu B.. 

 spirogyra was fairly common in this form. In this 

 modification the nuclear filament appears to be split at 

 certain points, thus giving rise to open loops in these places 

 (cf. fig. 32). 



Division takes place as in B. spirogyra (fig. 33). It will 

 be unnecessary therefore to describe it in detail. A number of 

 short forms (fig. 36), which measured about 7 /x in length, 

 were seen. They are apparently young forms resulting from 

 the transverse divisions of the long individuals, but some of 

 them may possiljly be anotlier species. 



This oi'ganism is — like B. spirogyra and the spirogyra 

 forms from Lace r ta — monosporic. It forms a single terminal 

 spore in each cell (see fig. 39). Details of spore-formatiou 

 were not observed, but it appears to take place in a manner 

 similar to that of B. spirogyra. 



