258 ENDOSPOREAE [DIASTEMA 



with the type from Maine, U.S.A., in capillitium and spores, but the 

 colour of the sporangia is dull brick-red instead of " gold bronze." 

 By the light of these specimens, that in Broome's Collection (B.M. 94) 

 marked " Physarum metallicum" is clearly the same species ; it is in a 

 fragile condition and as the capillitium breaks up when mounted the 

 characters are difficult to recognise, but the numerous broken points 

 of attachment to the base and upper wall of the sporangium, together 

 with the minutely warted spores, leave no doubt of its identity. The 

 date and locality are not given by Broome, but it is probable that it 

 was gathered at Batheaston in 1869 or 1870, as it stands in his collection 

 among other specimens correctly marked Physarum metallicum Berk 

 and Br. (syn. Margarita metallica) gathered there at that date. Dianema 

 Harveyi has appeared during a period of five years in the winter and 

 early spring near Lyme Regis, always in small quantity, upon dead 

 sticks of ash and clematis. It has been found repeatedly near Aberdeen, 

 by the Rev. W. Cran, on the bark of ash and fir in winter. In a 

 gathering made by him in January, 1911, the pulvinate sporangia 

 contain abundant capillitium ; the threads are rather stouter below 

 than above, they anastomose and branch freely, and are marked with 

 bead-like swellings. — M. Meylan has courteously sent us part of the 

 type of his new genus Lamprodermopsis — L. nivalis (Bull. Soc. Vaud., 

 xlvi. 56(1910) ). The sessile, pulvinate sporangia were gathered on turf 

 in the Jura Mountains at an elevation of about 4,000 feet, near 

 melting snow. The specimen sent us agrees in all essential characters 

 with the genus Dianema. It appears to be very closely allied to D. 

 Harveyi, from which it differs only in the capillitium threads being 

 rather stouter at the base where they radiate from the more central 

 parts of the floor of the sporangium, while above the slender tips of 

 the threads are easily detached from the sporangium-wall ; the spores 

 are greyish-pink in colour. M. Meylan writes that the sporangia are 

 sometimes mounted on pale stalks, "0 to 1 mm. high." These 

 characters can scarcely be regarded as of sufficient importance to 

 constitute generic distinction, and it would seem preferable, if the 

 distinguishing features prove constant, to place this interesting Alpine 

 species next D. Harveyi under the name of Dianema nivalis. 



Hab. On dead wood, and turf. — Lyme Regis, Dorset (B.M. 3161) ; 

 Aberdeen (B.M. 3162) ; Maine (B.M. slide). 



2. D. depressum Lister Mycetozoa, 204 (1894). Plasmo- 

 dium white, rarely rosy red. Sporangia solitary or clustered, 

 forming sessile pulvinate depressed plasmodiocarps, 2 to 10 mm. 

 wide, about 0-3 mm. thick, shining violet when immature, 

 glossy and grey-brown when mature ; sporangium-wall 

 membranous, smooth, translucent, yellowish- or lilac-grey, 

 marked on the inner side with the persistent ends of 

 the capillitium when the rest of the tlireads have fallen 

 away. Capillitium profuse, consisting of pale yellowish- 

 grey straight rigid slender threads, 0-5 to 2 fx thick, 

 forking at an acute angle, connected with each other 

 at the opposite ends, or fasciculate, without free branches, 

 minutely papillose on one side, attached above and below to 

 the sporangium-wall by the suddenly acuminate extremities. 



