KONGL. SV. VET. AKADEMIENS HANDL1NGAK. BAND 25. N:0 5. 147 



neric species D. aptogonum; both b and c are normally 'foraminated', as also are the 

 two succeding species. In the end view, the sides of D. Swartzii are eoncave. 



Hab. a, b, e, Bengal; a, Northern India; also Khasia, G. vox L. 

 2. D. Bengalicum, n. sp. (D. Swartzii var. />' Wallich Desm. Beng. pp. 189, 191, t. 

 VII, f. 2, 3, 1860; Mscr. No. 73, 1855). 



Habitu fere D. Sivart: ii Agdh., cellulis 1 ' / 8 -plo latioribus quam longis, medio non 

 profunde incisis; incisura mediana cuneate aperta interne rotundata, raro cuneata; api- 

 cibus in medio incavatis ('foraminatis') fasciis projicientibus truncatis; angulis latera- 

 libus rotundatis non angulatis nec dentatis; membrana glabra. A vertice visum tri- 

 angulare, lateribus medio distincte eonvexis, apud angulos parum attenuatis, angulis 

 rotundatis. Mensufae sunt: 



Long. 18—20, lat, 28, lat, apic. 15—16 ia. 

 » 17 , » 26, 12 u. 



» 19 , » 27, 14 u. 



» 16 , » 24, » 16 u. 



T. XIX, f. 1 — 3 a, W. B. T. ad nat.; f. 3 b — f after Wallich Mscr. 1. c; g. 

 cell. cum parasit, endophyt.? after G. C. W., descr. abest! 



The front view looks as though intermediate between D. Swartzii and D. apto- 

 gonum. It differs from both in front view in its rounded sides which are not at all 

 angular, and also from the latter in having the sinus of diverse shape; but in the 

 end view the diversity is most apparent, whereas that of the two species cited shows 

 decidedly eoncave sides, those of D. Bengalicum are decidedly convex. \\ith respect 

 to the cuueiform apical processes, (the 'cushions' of Wallich,) they do not appear to 

 me to exist in the young cells, but when older the 'foramina' appear between the 

 fronds, and with them the little processes come simultaneously. In specimens from 

 Khasia these processes were very narrowly cuneate. 



Bengal, G. C. W. 1855; Kast India, from Utricularia fasciculata ; Khasia, from 

 Utrir. sp. G. von L., 1889. 



3. D. aptogonum Bkeb. (Alg. Fal. p. 65, t. II, 1835! Menegh. Synops. p. 203, 1840; 

 Kltz. Phyc. Germ. p. 141; Spec. Alg. p. 190; UdonteUa desmidium Ehk. Infus. p. 

 153 pro p., t. XVI, f. 4, 1838; Aptogonum desmidium, Ralfs B. Desm. p. 64, t, 

 XXXII, f. 1, 1848; Breb. Liste, p. 119, 1856). 



Long. 15, lat, 26 .", after Wallich Mscr. No. 54 b. 



Although Wallich in Desm. Beng. has omitted this species, his sketch es in 

 Mscr. are unmistakeable. The sides protrude but little and the latera] angles are 

 nearly rounded; median incision small, acute; much like the Italian form represented 

 by Delponte (Aptogonum desmidium Delp. Desm. Subalp. t. III, f. 1). As in the 

 Europeän plant the sides, in th<; vertical view, are eoncave. The plane form (("i Ehren- 

 bergii Ktz. Sp. Alg. j>. 190; Aptogonum diagonum Delp 1. c, f. 6 — 10, has notbeen 

 observed in India. 



Bengal, G. C. W.; Kast Bengal, from U. fasciculata, G. v. L. 



4. D. Baileyi (Ralfs) Nokdst. (Alg. et char. p. 4, 1880; Alg. N. Z. p. 25, t. II, 1888; 

 Aptogonum Baileyi Ralfs Br. Desm. p. 208, t. XXXV, f. 1, 1848; Wallich Desm. 



