44 Floristik und Systematik der Phanerogamen. 



MOSS, C. E., Peat Moors o f the Pennines: Their Age, 



origin and utilization. (The Geographical Journal. 



Vol. XXIII. No. 5. 1904. p. 660—671. figs. 1 — 12.) 



The Pennine moors are oi three kinds, cotton-grass moors, which 

 are by iar the most extensive, heather moors and grassy moors, and 

 have already been described in detail by Smith, Rankin and the 

 author (Geographical Distribution of Vegetation in Yorkshire). There 

 is plenty of evidence to show, that the peat moors oi the present day 

 occupy the sites oi iormer iorests and it is probable, that this primitive 

 forest extended over almost the whole oi the Pennine slopes and over 

 much, at least, oi the Pennine summits. A great deal oi this primitive 

 forest was probably destroyed in Roman times and a great many streams 

 would be stopped near their sources by the interierence oi drainage by 

 the iallen logs: thus numerous and extensive swamps would soon arise 

 over the more level regions. Bog-forming mosses, which are abundant 

 in the upland woods, would soon take possession oi the morass and such 

 places would act as centres, from which marshes would radiate in all 

 directions, even over areas not quite so ilat. It is noteworthy that many 

 plants iound to-day in lowland peat bogs do not occur on or in the 

 upland Pennine peat-moors (e. g. Typha, Iris, Sparganium etc.), so that 

 this stage, irequently observed in the lowland bogs, has probably been 

 altogether omitted in the case oi the peat moors of the Pennines. On 

 the slopes, owing to the better conditions oi drainage, the destruction 

 of the primitive Pennine woodlands did not give rise to morasses, and 

 the original iorest would gradually rejuvenate. Peat iormation on many 

 of the Millstone grit rocks, which emerge from the surface of the general 

 peat, may be observed in actual Operation to-day and proves that peat 

 may sometimes be formed with no pre-existing pond or swamp. On a 

 layer of slimy blue-green or green Algae or of small Lichens or of both 

 combined (moor-pan) mosses become established, which grow rapidly 

 in an upward direction and form a layer of peat very quickly. Even 

 over extensive areas however, peat does not necessariiy accumulate at 

 the rapid rate, which probably occurred in the case of the deep peat on 

 the cotton-grass moors of the Pennines, as is especially shown at the 

 edges of these latter moors. The accumulation of the shallow peat found 

 here seems to have been preceded by the formation of moor-pan (slimy 

 Algae, Lichens, small liverworts and small mosses), which furnishes an 

 impervious layer on which heath plants can successfully hold their own. 

 It thus seems as though the deep peat accumulates quickly, the shallow 

 peat slowly and both are probably of about the same age. 



F. E. Fritsch. 



Nelson, Aven, New plants from Nevada. (Proceedings 



of the Biological Society of Washington. XVII. April 9, 1904. 



p. 91—98.) 



Arabis pedicellata , Viola senecta , Mirabilis glutinosa, Sidalcea 

 crenulata, S. nervata, Sphaeralcea parvifolia, Sphaerostigma tortuosa, 

 Phacelia monosperma, Meüensia nevadensis, Pentstcmon violaceus (P. 

 Roezli violaceus Brandegee), P. Kcnnedyi, and Lagophylla Hilbnani. 



Trelease. 



Probst, R., Im Zickzack von Stühlingen über den 



Randen zum Zollhaus. (Mitt. Bad. Bot. Ver. 1904. 



No. 191 u. 192. p. 345—360.) 



Eine floristische Studie in Form einer Excursionsbeschreibung, die 

 auch auf den geologischen Aufbau des Gebirges hinweist und in 

 pflanzengeographischer Beziehung auf das häufige Vorkommen politischer 

 Steppenpflanzen in der Umgebung von Stühlingen aufmerksam 

 macht. Schindler. 



