Floristik, Geographie, Systematik etc. 235 



sp. ..Mähren), eine Serie von Epilobium-Ba.sta.rden, viele Gräser, 

 Thymus- Arten , Pteridophyten. — Die Sammlung wird fortgesetzt. 

 Dem Werke werden Scheden beigelegt. Matouschek (Wien). 



Petrak, Fr., Ueber neue oder wenig bekannte Cirsien aus 

 dem Oriente. (Oesterr. bot. Zeitschr. LX. N°. 9. p. 351—356. 

 N". 10. p. 393—296. N°. 11. p. 436—441. N°. 12. p. 459-463. 1910.) 

 Als neu werden beschrieben: 



Cirsium Boujartii (Pill, et Mitt.) C. H. Schultz subsp. n. Wett- 

 steinii (Albanien;; C. Vandasü n. sp. (Balkan, das dort fehlende C. 

 eriophorum stellvertretend); C. ligulare ßoiss. subsp. n. paueidentatum 

 (Bithynien); C. turkestanicum n. sp. (Turkestan); C. congestum Fisch, 

 et Mey subsp. n. afghanicum (Afghanistan); C. steirolepis n.sp. (N.-W. 

 von Kleinasien, dem C. bulgaricum nahestehend); C. fimbriatum 

 (MB.) Spreng subsp. n. Bornmülleri (Rossia, Tauria); C. hygvophilum 

 Boiss. subsp. n. elbrusense (Nordpersien); X C- fraternum DC. X 

 Haussknechtii Boiss. n. hybrid, in den Formen chloroticum und 

 eriophyllum (Westpersien); C. strigosissimum Petr. et Bornm. n. sp. 

 (Persien?, am nächsten C. aristatum DC. stehend); C. caspicum Petr. 

 n. sp. (Kaspische Region); C. tymphaeum Hausskn. 1895, vielleicht 

 ein Bastard von C. canum und C. depilatum Boiss.); X C. pindicalum 

 Hausskn. (= C. siciilum X tymphaeum) n. hybr. (Berg Baba); C. 

 apiculatum DC. subsp. n. glaberrimum Petr. (Transkaspien); C. sicu- 

 tum Spr. subsp. n. Gaillardotii Petr. (= C. Gaillardoti Boiss. 1856) 

 [x\sia orientalis]; C. desertovum Fisch, subsp. n. vir ide Petr. Zu dieser 

 Art gehört C. viride Velen. C. Libanoticum DC. ist kein Synonym 

 zu C. apiculatum DC. Matouschek (Wien). 



Prankerd, T. L., On the Structure and Biology of the 

 Genus Hottonia. (Ann. Bot. XXV. p. 253—266. 2 Plates and 7 

 Text-figures. 1911.) 



A description of the external morphology and the life-history 

 of the two species of the genus Hottonia is given, and the origin 

 of the so-called "land-forms" is discussed. The anatoiny of the 

 mature stem shews a considerable divergence of structure in its 

 different regions. The young plant is characterised by a haplostele, 

 whiie in older parts a medullated stele is present. The land forms 

 are similar as regards their vascular tissue to the submerged parts 

 of the aquatic plants, and differ from the aerial parts which . in 

 their internodal regions, have a ring of V shaped bundles. A 

 polystelic phase oecurs where the transition from the aquatic to the 

 aerial type of structure is taking place. In H. palustris the polystely 

 is found at the base of the inflorescence axis, while in H. inflata 

 more or less perfect steles are formed from arcs of vascular tissue in 

 the lateral inflorescence axes near their junetion with the main stem. 



The author considers that the transient polystelic condition of 

 the two species of Hottonia lends support to the theory that an 

 aquatic ancestral existence is the origin of some, if not all, cases 

 of polystely in Dicot) r ledons. 



The anatomy of the leaf and root is described, and certain 

 pecularities in the position of the latter are pointed out. The ana- 

 tomical structure of the minute seedlings is very simple; the tran- 

 sition trom stem to root structure takes place high up in the hypo- 

 cotyl and is in aecordance with Van Tieghem's type III. 



E. de Fraine (London ;. 



