KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 55. N:0 5. 



119 



"-str 



.ep 



The few ripe fruits seen are in form and size like small fruits of the last mentioned 

 species. The peduncles are 15 — 25 mm long. The colour of the plant is at first 

 dark-green, as in P. trich., but turns finally into brown (P. obtusif.). Beside the 

 colour and apexes of the leaves, their strong mechanical strands stand decidedly up 

 for P. trichoides as the one of the parents of this hybrid. 



The plant described above is gathered by Foucaud in France, Charente-In- 

 ferieure, Marais du Four-du-Diable pres Echillais, 52 (hb. Stockholm.) and in the 

 same station in 1890 by Jotjssbt and Foucaud (hb. Lund.). By French authors 

 considered to be P. Berchtoldi Fieb. 



A plant from Hercecjovina, Buna-river, gathered ("/' 1889) by Prof. S. Murbeck 

 (hb. Stockholm., Uppsal., Lund.) is also the same hybrid. It lacks turios but all 

 its properties are intermediate between the two above written species. The affinity 

 with P. trich. is especially evident anatomically 

 as well as morphologically. From this firm 

 starting point the other partner can easily 

 be traced in the leaves and ligules. 



No other stations for this bastard are 

 known to me. — 



P. obtusifolius is said to occur in The 

 Himalayas (ex Bennett, in Graebner, Pot. 

 1907, 161). 1 have seen the specimens here 

 concerned, collected by D:r Brandis, 1864, 

 n:r 3333 and now preserved in Calcutta, 

 India. This plant, standing very close to 

 the new American species below, and perhaps 

 only a broad-leaved variety of this, certainly 

 has the habit of P. obtusifolius, to which can 



be added that the size and form of the leaves also correspond pretty closely to that 

 species, but their nervation and inner structure is quite different. The leaves are 

 about 2 mm broad and 3-nerved, the lateral nerves join the midrib a leaf-width beneath 

 the point and the midrib is accompanied up to the very apex by a richly developed 

 lacunar system, never occurring in P. obtusifolius. The stem is nearly terete, the 

 epidermis without supporting layer and the cortex has two circles of large lacunae. 

 The central cylinder is of a circular diagram type with the bundles fused together into 

 a compound bundle with a common xylem-channel. 



I have not the plant at hand now, so that I am not able to give a full de- 

 scription of it — the specimens mentioned lacked fruit — , but the above characters 

 are nevertheless sufficient to distinguish it from all the other Pusilloids. From P. 

 Henningii, of Caucasus, it differs by narrower leaves with fewer lateral nerves, be- 

 sides which P. loculosus has a more easterly distribution. Leaving a couple of 

 sketches of this species also I propose to name it: 



1 



Fig. 52. P. Joculosits Hagstr. J, Top 

 of a leaf showing the nervation and tlie 

 areolation, ^. B, Transverse section of stem, 

 cc, central cylinder, sir, mechanical strands, 

 /, lacunffi, ep, epidermis, ca. \^. 



