72 BOTANICAL GAZETTE [jqly 



Druidioxd (Kew Bull. 1907:90-92) has described a new genus {Chlamydites) 

 of Composltae from Tibet. — H. D. House (Muhlenbergia 3:37-46. 1907) has 

 described 15 new species of Ipomoea from Mexico and Central America. — Rehder 

 (Ehodora 9:60-62/ 1907) has published a new variety of Quercus prinoides 

 from Mass. and N. J. — Finet and Gagnepain (Bull. Soc. Bot. France IV. 6:55- 

 170. pis. g-20. 1906), in continuation of their Flore de VAsie orientale, have 

 presented the Anonaceae, including 25 genera represented by 249 species, 2^ of 

 which are new. — O. E. Jexxings (Ann. Carnegie Mus. 4: 73-77. pi, 20.1906) has 

 described a new species of Lonicera (L. aUissima) from Penn. — H. D. House (Bulb 

 Torn Bot. Club 34:143- 155. 1907), in his third paper on N. Am. Convolvulaceae, 

 has described a new species of Calycobolus. — K. K. Mackenzie {ide^n 151-155) 

 has described 4 new western species of Carex. — W. W. Rowlee {idem 157-159) 

 has described 2 new species of Salix from the Canadian Rocky Mountains. 

 J. M. C. 



Riella and Sphaerocarpus. — In the eleventh of his Archegoniatensludien 

 GoEBEL discusses germination and regeneration in these aberrant liverworts/ =* 

 in extension of the investigations recorded in no. iv. Having an abundance of 

 living material, Riella being easily cultivated, he is able to show that the peculiar 

 "wing** of Riella is not an ^'outgrowth" from an earlier-formed midrib, but that 

 the germ-disk lies in the same plane as the wing and expands directly into the 



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plant (homoblastic development), as soon as the intercalary growing point is 

 organized and becomes active. 



Herein he controverts Solms-Laxjbach and Porsild, who seem to consider 

 the development as heteroblastic, holding that the thallus arises, as a dififerent 

 structure, so to speak, from the germ-disk (which SoLMS called protonema and 

 PoRSiLD the primordial lobe), much as a sphagnum stem arises from its pro thallus. 

 GoEBEL(who, however, denies any special interest in such a question), in agree- 

 ment with Porsild but contrary to Solms, finds no wedge-shaped apical cell in 

 the growing point until a late stage of development. When after injury or under 

 bad conditions adventive shoots are formed, whether on the thallus or germ-disk, 

 there is first the production of simple one-layered regions like the germ-disks, i.e., 

 secondary disks, and from these the new thalli arise directly, as in sporelings. 



In Sphaerocarpus the spore produces a germ tube, which at its end becomes 

 a multicellular cylinder with a depressed tip. From one quadrant of the cupped 

 end the vegetative point arises and from two others the wings proceed. The germ 

 cylinder thus produces the thallus homoblastically. In adventive shoots the same 

 phenomena recur, Goebel confirms Leitgeb's statement as to the precocious 

 formation of sex organs, plants only o.i™"^ shovrmg their rudiments. ^^ The 

 largest sterile thallus found (and this was far beyond the usual) was i"^™ long. 



C. R. B. 



la GoEBEL; K., Archegoniatenstudien. XI, Weitere Untersuchungen liber Kei- 

 mung und Regeneration bei Riella and Sphaerocarpus. Flora 97:192-214. fgs. 23- 

 1907. 



*3 Misquoted by Campbell, Mosses and Ferns, 2 ed., 82, as "one millimeter." 



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