BY G. I. PLAYFAIR. 359 



tion from the granules, and not by any colouring matter. B. 

 ulna is very rare; I remember to have noted it only once before. 



Spirillum volutans Ehr. 

 Anfract. diam. 7, alt. 12; fil. diam. H /x. 

 Lismore(178, 186, 187,233). 

 This is exactly the size of Cohn's broadest figures. 



Var. MAXIMUM Playf. 

 Anfract. diam. 14, alt. 24; fil. diam. 1| /ot. 

 Lismore(233). 



The spirals are twice as broad as in the type, cf. Biol. Richm. 

 R., p.l39, PI. vii., f.8. 



Spirillum laxissimum Playf. 



Long. 10; fil. diam. 1 /x. Anfracti- 

 bus singulis. 



Lismore (236, 259). 



Cf. Biol. Richm R., p. 139, Pl.vii., ^ig.lO. 



f.lO. Spirochceteplicatilis{UO), and Spiroch.He plicatilis Ehr.; 

 Vibrio serpens were also observed. 



EXPLANATION OF PLATES XLI. XLVI. 



(All figures magnified 665 diameters, unless stated otherwise.) 



Plate xli. 

 Fig. 1. — Gonatozyyon moiiotceniuni var. tenue, n.var. 

 Fig.2. ., Biebissonii var. minutnm \V. & G. S. West. 



Fig.3. — Peninm maygaritacenm var. pulrerithntnm, u. var. ; ( x 500). 

 Figs. 4, 5. ,, ,, var. i?idiui\<«?im, u.var. ; ( X 500). 



Fig.6. ,, cucAirbitiiium van-, suhpolymorphum i. o'as.sior, n f. ;( x 350). 



Fig. 7. — Closterium Spetsbergense var. palnstre, n.var.; tip. 

 Fig. 8. ,, yracile var. suhstrxgosum (Rac.) mihi. 



Fig. 9. ,, ?>ro7mm Breb. ;{ x 335). 



Fig. 10. ,, jorce^07iytim Breb. ; tip of Australian form. 



Fig. 11. — Mixed form, (a) Cosmarium nctangulare var. nodulatum f, minor 



Playf., (6) Cos. rtct. var. Boldtii f. minor, n.f. 

 Fig. 12. — Cosmarium rectangulare var. biretnm, n.var. 

 Fig. 13. ,, ,, ,, ,, f. rectilinearis, n.f. 



Fig. 14. ,, ,, ,, ,, i. anyuslior, u.i. 



