K0NGL. SV. VET AKADEMIENS HANDUNGAR. BAND. 22. N:0 8. 51 



Membrana granulata granulis in series horizontales et trausversas (plus minus evidenter) 

 quincuncialiter ordinatis, seriebus 2 inferioribus exceptis, quae in costas verticales bigra- 

 nulatas coalitaj sunt, Nuclei amylacei singuli. 



Long. 46 — 53 ,»; lat. 26 — 30 ,«; lat. isthm. 16 — 22 f-i; crass. 18 — 19 ,«. 



Omatangi (240, 248, 257, 258). 



The description of Co sm. pseudamoenum by Wille 1. c. is very short, probably be- 

 cause he had only inet with a few cells that werc not empty. It may be distinguished 

 froin Gosm. amoenum by the large isthmus, by the arrangeinent of the granules and by 

 single amylaceous vesicles. Cosmarium inornatum Josh. Burm. Desin. p. 648, tab. 24, 

 tig. 26 et 27 I must regard only as a variety of C. pseudamoenum. 



12. C. (listichum nov. sp. Tab. 5, tig. 16. 



C. medio sinu lineari profundo constrictum; long. : lat. — 1:1,14 — 1,22; semicellula? 

 transverse subrectangulari-ellipticte basi lata, dorso sublato truncato, lateribus paullo con- 

 vexis, angulis inferioribus subreetis, superioribus late rotundatis, margine laterali utrinque 

 6-undulato-orenato (apicali integro), in centro granulis majoribus 7 (1 centrali paullo supra 

 medium semicellulie, 6 periphericis distantibus) prseditae; a latere visa; circulares apice 

 medio truncatas, margine utrinque granulis 4, e supremo granulo utrinque serie granulo- 

 rum 5 ad basin se extendente (seriebus deorsum convergentibus); e vertice visas late el- 

 lipticaä medio utrinque margine granulis o (et inträ 2), 2 seriebus granulorum distantibus 

 longo spatio mediano abruptis (granulis in utraque parte 4), inter apiees se extendentibus. 

 Membrana ceterum punctata. 



Long. 38 — 40 ,«; lat. 28 — 35 ,u (ad basin circ. 25 — 28 f-i); lat, märg. term. 24 ,«; 

 crass. 24 ,u; lat. isthm. 10 ,«. 



Taupo (154); Omatangi (240). 



This species belongs to the section distinguished by 2 series of granules in the margin 

 of the semicell, which may best be observed in the end or side vie\v, and by one or 

 several granules in the centre of the semicell in the front view. To this section belong 

 C. cristatum Ralfs, C. monomazum Lund., C. polymazum VVolle (?), C. Donellii Wolle. 

 C. distichum which is perhaps nearest to C. cristatum may be known by an interruption 

 in the series of granules, so that the end itself is without granules. C. cuneatum Josh. 

 Burm. Alg. p. 647, tab. 24, tig. 17 & 18 forms a transition to the section provided with 

 several similar series of granules or tubercles, such as C. Kitckelii Wolle, C. quadri- 

 farium Lund. Near to this section also is C- spinosum Josh. having no granules in the 

 centre of its semicells. 



13. C. brasiliense (Wille); C. sphalerostichum Nordst. />' brasiliense Wille Sydam. 



Alg. p. 15, tab. 1, tig. 30. 



fi taphrosporum M nov. var. Tab. 5, fig. 17. 



Seniicellulaä isthmo paullulo elongato connexfe, sinu amplo discreto, oblongaä utroque 

 fine rotundatai, dorso late subtruncataSj ventre subconvexre (isthmo excluso), margine ex- 



') Tv.maot; = fovea. 



