Arctic Plants: Morphology and Synonymy 45 b 



white petals with purple dots above, and not unguiculate at the base; stamens 

 shorter than the corolla; and smaller capsule with much shorter styles. It 

 probably includes all of the so-called S. bronchialis from the Rocky mountains 

 south of Alaska." 



Some specimens which I have before me, collected by Mr. Crandall on 

 Pennock's mountain ranch in Colorado (altitude 7,500 feet) agree exactly with 

 the distinction pointed out by Dr. Wiegand,' but I do not believe these dis- 

 tinctive characters are sufficient for the establishment of a new species. 



Professor Engler in his excellent monograph of the genus (I.e. p. 215) calls 

 attention to the variability of S. bronchialis L. corresponding with that of S. 

 aspera DC, of which the alpine form is more densely caespitose, and with the 

 inflorescence few-flowered in contrast with the plant from lower elevations. 

 Finally, if we compare S. flagellaris Willd. as represented in the north and 

 south, we notice quite a prominent difference in the relative size of flower and 

 fruit, the structure of the foliage, etc., but without feeling inclined to divide 

 the species. From the experience I have had with Saxifraga, especially in the 

 field, I should prefer to consider S. austromontana Wieg. as a form of *S. bronchialis 

 L., instead of an independent species. 



S. aizoides L. Several complete specimens were collected by the expedition, 

 "complete," because in several of the specimens the primary root was preserved. 

 However, the arctic plant differs from the southern by its more condensed growth; 

 quite compact cushions may be developed, measuring in width about 7 cm., 

 not including the flowering stems. Among those from Bernard harbour some 

 specimens are of quite diminutive size, barely 2 cm. high, and it is in such speci- 

 mens that the primary root was present; it is relatively deep, but slender, and 

 emits several branches; secondary roots develop freely from the subterranean 

 stems. In the southern plant the stems are more spreading, in the manner of 

 S. Hirculus, but typical stolons with scale-like leaves were not observed. In 

 the arctic plant the leaves are much crowded and the shoot is quite profusely 

 ramified; thus a cushion may be formed. Vegetative reproduction is secured by 

 means of the lateral shoots, which may be separated from the mother-plant and, 

 by their ability to develop secondary roots, new individuals may thus be formed. 



S. flagellaris WiUd. 



This is one of the most interesting species of the genus. We find it in the 

 polar regions as well as in the alpine, and exhibiting principally the same morpho- 

 logical structure. The arctic plant is generally of very low stature, the flower- 

 bearing stem reaching a height of only 1 J to 3 cm. The shoot bears a number of 

 fleshy leaves, glandidar hairy especially along the margins, and these leaves 

 form a small rosette resembling that of a Sempervivum. In spite of the yery 

 considerable material which I have examined, there is not a single specimen 

 showing a persistent primary root; the root-system consists only of a number of 

 secondary roots, developed from the basal internodes of the rosette. A single 

 flower-bearing stem, bearing a few leaves and one or two flowers, terminates 

 the shoot. Very characteristic of the species is the development of long runners 

 above the ground, consisting of a single internode, reaching a' length of about 

 10 cm., and terminated by a small spherical rosette of green leaves; these runners 

 are developed in the axils of the rosette-leaves. When the fruit is mature the 

 main shoot dies off and at this time, towards the end of the season, the rosettes 

 borne on the runners have commenced to develop roots; as the runners die off 

 with the mother-plant, these rosettes thus become independent individuals and 

 repeat the growth of the mother-shoot. I do not know how long time these 

 rosettes require to become mature to produce flowers, but judging from the size 

 of various specimens which I collected in Nova Zembla, I presume they reach 

 maturity in the third year. 



TbuU. Torres Bot. Club. Vol. 27, 1900, p. 388. 



