15 
13. Isipinga Doidge, nov. gen. Polystomellacearum. 
Mycelium superficialum, ramosum, septatum, hyphopodiatum. Stromata super- 
ficialia ex hypostromate subcuticulari oriunda, pluries affixa. Loculi inordinate dispositi, 
rotundati vel elliptici (non lineares). Asci paraphysati, octospori. Sporae phaeodidymae. 
This genus differs from Hysterostoma Theiss. in the presence of a well-developed 
aerial mycelium, and from Asterodothis in the absence of a central column or foot. 
Isipinga areolata n. sp. 
On leaves of Euclea natalensis, Isipingo Beach, Natal, 21.5.17, Doidge [10153] ; 
13.5.13, Doidge [6647]; near Durban, Natal, 25.5.97, Medley Wood [9520] (Wood 
No. 6447); 25.5.15, Doidge [8986]; 13.1.18, V. d. Byl [11363]. 
, Hypophyllous, usually near the reflexed leaf margin, less frequently scattered over 
the whole under-surface of the leaf, forming circular, dull-black areas, 5-15 mm. diam., 
often coalescing and forming irregular black blotches, especially along the leaf margins ; 
stromata scattered and visible as small denser black points. 
Aerial mycelium well developed, hyphae fuscous, 3-5-5 u thick, branching freely and 
anastomosing to form regular, circular, or slightly oval areolae, 30-50 » diam.; hypho- 
podia unicellular, darker than the hyphae, ovate or ellipsoid, straight or curved, 8-10 OK 
5 u. Stromata scattered, circular or oval, opaque black, 300-350 u diam.- or about 
400 u x 240 u, formed of radiating cells; arising from a subcuticular hypostroma which - 
breaks through the cuticle to form the stromata in the cavities above the sunken stomata ; 
stromata attached to host at several points by dark brown or black fungous pegs, which 
are up to 20 u thick where they penetrate the cuticle ; height of fruiting body 1 is 80-100 p, 
each stroma containing several round to irregular loculi ; the dark covering membrane 
slopes gradually towards the leaf surface at the circumference of the stroma. -Loculi 
dehisce at maturity by irregular fissures in the covering membrane. 
Paraphyses fairly numerous, hyaline, linear, about 3 » thick, slightly EE the. 
asci. ‘Asci eight-spored, ovate or broadly ellipsoid, thick walled round apex, 50-65, (ra 
33-40 u, not reacting to iodine, but staining a sort of brick-red colour. Spores tristichous 
or conglobate, brown, two-celled, 27-32 u x 13-13-5 u, constricted, upper loculus larger. 
Isipinga areolata Doidge, n. sp. 
‘Mycelium hypophyllum, bene evolutum, ramosum, areolatum ex hyphis 3-5-5 u 
crassis, anastomosantibus, hyphopodiis continuis, ovatis v. ellipsoideis, rectis v. curvatis, 
8-10 u x 5 u, compositum. Stromata sparsa, rotundata v. elliptica, atra, opaca, 300-350 u. 
diam.; v. elliptica, circ. 400 u x 240 u, radiatim contexta, hypostromate subcuticulare 
oriunda, pluries affixa. Loculi inordinate dispositi, 80-100 » alti. Asci octospori, ovati 
vel late ellipsoidei, 50-654 x 33-40 u, paraphysate; paraphysibus filiformis, hyalinis, 
3 pu. crassis. Sporae tristichae v. conglobatae, brunneae, 1-septatae, 27-32 u x 18-13 5 u, 
constrictae loculo supero, paullo majore. 
- Hab. in foliis Eucleae natalensis, Isipingo, Natal, 21.5.17, leg. Doidge [10153]. 
14. Isipinga contorta Doidge. 
Syn. Dothidasteromella contorta Doidge, Trans. Roy. ane. of S.A. VIII, Part 8, 1920. 
On leaves of Trichocladus ellipticus, Branders’ High Forest, Victoria East, 14.8.15, 
V. d. Bijl [9462]; Pirie Forest, Kingwilliamstown, 8.7.19, Doidge [12298]. 
Forms small, dull-black, round, or irregular areas on upper surface of the leaves; 
the leaf tissues become discoloured in the neighbourhood of the fungus, right through to 
the lower epidermis. Aerial mycelium well developed, primary hy phae long, radiating, 
fuscous, 3-3-5 thick, with unicellular hyphopodia which are alternate or unilateral, 
subglobose, 6-7 u diam.; between the radiating hyphae there is a densely interwoven 
mass of paler secondary hyphae which are very tortuous and crumpled, copiously branched, 
and anastomosing. Stromata scattered, opaque, black, 250-350 u diam., with radiating 
structure, unilocular, attached at several points, and arising from a well-developed sub- 
cuticular hypostroma. Asci paraphysate, ellipsoid, or ovate, very briefly stipitate, straight 
