40 THE JOURNAL OF BOTANY 
exactly as in D. glyptosperma, but the shortness of the cells and the 
absence of the filamentous condition recall very much the conju- 
gation in the genus Cylindrocystis. When apiceenaleielt maturity 
the zygospore still ad hatiivelnsd to it the four halves of the two 
gametangia, and these four half-cells acquire that remarkable 
appearance of solidity which is such a striking feature in the 
conjugation of D. glyptosperma (cfr. Ann. Bot. vol. xii. p. 49, 1898). 
each being a metamorphosed half-cell of the two gametangia. This 
is exactly the appearance which is most conspicuous in the conju- 
gation of D. glyptosperma, and whi ch, apart from other ae 
would be sufficient to place this alga in the genus Debar 
24. ZyenemaVavcuenrt Ag. var. staGNaLE (Hass. ) Kirchn. a 
fil. 11°5-18 »; long. zygosp. ngera bs lat. zygosp. 15°3-16°3 
Hab. Near the Lizard, Cornw 
The vegetative cells were 5-7 t shal longer than their diameter, 
and the fructiferous cells were slightly swollen. The zygospores 
had the appearance of being arranged in pairs owing to their 
position towards the contiguous ends of every pair of fructiferous 
cells. 
25. Genicutaria sprrormnta De Bary. Long. cell. 270-355 p; 
lat. cell. in med. 2 23-25 pw, ad apic. 27-29 u; diam. zygosp. 54-57 p 
Hab. Hayle Pool, about four miles from the Lizard, Voriae 
This rare  Deamia has been observed from Cornwall once before, 
but is not known from any other part of the British Islands. 
specimens seen there were two large spiral chloroplastids with 
rregular arg ae large pyrenoids, each chloroplastid making 
fons 54 to 74 tur 
enicularia is ne rarest of all the genera of Desmids. 
on Sprrorayia minuta Thur. Hab. Llyn Idwal, N. Wales. 
. 8. parvuta Arch. Hab. Glyder Fach, N. Wales, at 2200 ft. 
“et Mesoranium Enpuicuertanum Nig 
Hab. Bog below Llyn Idwal; Glyder Fach, at 2200 ft., N. Wales. 
Var. Grande Nordst. Hab. Capel Curig, 'N. Wales 
29. M. mrriricum Arch. Hab. Llyn Idwal, N. Wales. 
30. um Lisetiuta (Focke) Nordst. var. irermeprum Roy 
SS Hab. Bog above the lakes at Capel Curig; Llyn Tawal, 
fleriute Nicetu (Bréb.) nob. fe 2 a N. bor 
. N. optoneum (De Bary) Liitkem. var. 
(Pl. “146, fig. 10.) Var. cellulis minoribus ot exacte ale tplinilblate, tr 
reams chromatophoris ut in forma typica. Long. 57-78 »; 
Hab. Bog above the lakes at oe Curig, Moel Siabod, Llyn 
Taal, 1 he Cwlyd, Llyn Gwynant, N. Wales; Helvellyn, West- 
aa Mees 2 is often abundant in the boggy portions of upland 
d the margins of lakes, &c., frequently occurring mixed 
with t the | ‘ypisal plants. It is distinguished from the latter by i 
