646 MB. W. JOSHUA ON BUBMESE DESMIDIKiE. 



delicatis regulariter et symmetrice dispositis, spatio lucido ovato 

 ad centrum cujusve cellulae: isthino latit udine inter | et £ partem 

 diametri8 transversi. Longit. 88 /i, latit. 65 fi : isthmi latit. 16 it. 



Semicells with fine granules regularly and symmetrically 

 arranged, with a clear oval space in centre of each cell 20 it by 

 13 tt; without central inflation, deeply constricted (width of 

 isthmus between the fourth and fifth part of transverse diameter). 

 Differing from C. Botrytis, /3. onesoleium, Nordst., in the narrow 

 isthmus and arrangement of granules. Length 88 ft ; breadth 

 65 fx ; width of isthmus 16 ft. 



C. tetbaophthalmum, Kutz. 



C. amcenum, Breb. 



C. Meneohinit, Breb., and forms. 



C. pybamidatum, Breb. A variety with slight inflation in 

 semicell. 



C. latum, Breb. 



C. Palangula, Breb. 



C. CONSPEBSTTM, Ralfs. 



C. Diadema, n. sp. (Plate XXV. fig. 7.) 



C. magnum, fere l|-plo longius quam latum, cylindricum: 

 semicellulis leviter constrictis, late marginatis, granulis magnis in 

 seriebus equidistantib'us dispositis, intersticibus minute punctatis. 

 Longit. 75 ft, latit. 50 it. 



Large, nearly 1| times longer than wide, cylindrical ; semi- 

 cells slightly constricted, with wide marginal band; granules 

 large, symmetrically placed in equidistant rows, minutely punctate 

 in interstices. Length 75 ft ; breadth 50 ft. 



C. BECTANGULABE, Grutl. 



C. globostjm, Bulnh. 



C. nobimbebgense, Beinsch. 



C. abmatum, n. sp. (Plate XXIV. figs. 21-25.) 



C. parvum, subhexagonale, nonnihil longius quam latum, con- 

 strictione lineari, recta : semicellulis trapezoideis, basi latis, apiee 

 truncatis, prominentiis obtusis 7-13, in serie interiore dispositis 

 (ad basin poli multo majoribus); marginibus prominentiis validis 

 conicis, 4-5 utroque latere fimbriatis, dorso nudo : cellulis multum 

 inflatis, a latere conspectis sphsericis. Longit. 35 ft, latit. 25/*: 

 isthmi lat. 8| ft. 



Small, subhexagonal, rather longer than wide ; median division 

 a straight line ; half-cells trapezoidal, with wide base furnished 



