98 SUMMARY OF CURRENT RESEARCHES RELATING TO 



deprive it to a great degree of its diatliermancy, so that the fragrant 

 clouds which iu a dry neighbourhood spread themselves above 

 odoriferous plants, protect them no less from the parching rays of the 

 sun than from nocturnal radiation. 



Detmer's Vegetable Physiology.* — The second part of W. 

 Detmer's ' System of Vegetable Physiology,' which forms a part of the 

 ' Encykloppedie der Naturwissenschaften,' treats of the following 

 subjects : — The general properties of the growing parts of plants, and 

 the nature of the process of growth ; the phenomena of growth caused 

 by internal conditions of growth ; the essential conditions of growth, 

 and the influence of external conditions on growth ; the natural 

 direction of the parts of plants ; and the movements of variation, 

 that is, those which take place only in the mature parts. 



B. CRYPTOGAMIA. 



Crypto gamia Vascularia. 



Chaetopterideae.j — M. Kuhn divides the large order of Polypo- 

 diacese primarily into the two groups of the smaller Chastopteridege 

 and the larger Lopidopterides. The former are distinguished by the 

 creej)ing rhizome having only a single closed vascular-bundle-tube, 

 and being covered only with delicate few-celled palete ; while the latter 

 have an erect or creeping rhizome, penetrated by one or more fibro- 

 vascular bundles which do not form a closed tube, and bearing 

 scaly palea> instead of hairs. The following is an analysis of the 

 tribes : — 



Ch^topteride^. Ehizoma repens, setosum; palese e paucis cellulis 

 formatae, quasi setfe Hymenophyllacearum, basi plana affixae ; tubus 

 fasciculi vasorum in rhizomate semper clausum. 



A. Sori exindusiati. 



Tribus I. Gymnogrammece. 



B. Sori indusio vero s. spurio obtecti. 



Tribus II. Lindsayece. Sori in apice nervorum s. in ana- 

 stomosi nervorum complurimum indusio obtecti ; recep- 

 taculum nullum ; margo immutatus, non revolutus. 



Tribus III. Lonchiticlece. Sori semper in anastomosi 

 nervorum, margine revoluto (indusio spurio) obtecti ; 

 indusium verum minutissimum, basi anastomosis ner- 

 vorum affixum. 



Tribus IV. Mkrolepiece. Sori singuli apicales s. sub- 

 apicales, margine revoluto s. indusio infero vero obtecti ; 

 receptaculum liber um. 



* Sclienk's ' Handbuch der Botanik,' ii. (1882) pp. 447-555. Cf. this Journal, 

 ii. (1882) p. 223. 



t Festschrift z. 50 jahr. Jubil. d. Konigstiidt. Realschule zu Berlin, pp. 

 321-48 (2 pis.) 1882. See Bot. Centralbl., xii. (1882) p. 188, 



