301 OBIGINAL ABTICLES. 



of oxalate of lime. — Eegnault. Aim. Se. Nat. Ser. iv. xiv. 118. 

 — Dianthus. The wood is distributed in two, three, or more con- 

 secutive zones, often inten^upted, or broken into fragments, in 

 transverse section, by more transpai'ent and wider belts of elon- 

 gated, attenuate, delicate cells with numerous slit-marked vessels. 

 Medullary rays are absent. Stellate crystals of oxalate of lime 

 abound in all the parenchym. In Arenaria rigida the form of the 

 woody masses is very irregular ; they include no vessels, these 

 being confined to the iuvading, thin-walled, fibroid tissue. Silene 

 pseudo-otifes has a nearly continuous wood without alternating 

 opaque and transparent zones. The modification of structure in 

 Gypsophila saligna, is also described. — Acanthophylhtm squa- 

 rosum. Boiss. This is the A. spinusum of Kotschy, and of my 

 paper in the Liiinean Transactions. M. Eegnault's observations 

 (1. c. p. 73) led me to re-examine sections of this plant. I have 

 to confirm my previous observations referred to above, on the 

 occurrence of true (uni'oUable) spiral- vessels in the wood-zone of 

 young branches, mtermediate to the yet distinct pith parenchyma, 

 and the cortical tissue. Slit-marked vessels traversing paren- 

 chyma, constitute the mass of the ' wood,' and the spirals require 

 to be carefully distinguisshed from them. These spirals are of 

 both extremely minute and tolerably wide calibre, the latter 

 nearly equalling in size the prevaiHug gashed vessels. I am not 

 prepared to say positively that the spiral vessels occurring in the 

 young stem (prior to the general derangement of its tissues) are 

 arranged in concentric and narrow rings, as in the paper above- 

 noticed I suggested they might be. — Acanthoplnjllum (Grriffith's 

 Affghan Coll. 15G2) possesses very numerous spiral vessels of 

 small calibre. These accompany the slit-marked vessels which 

 form the bulk of the wood. I continue to think they may be 

 more or less distinctly disposed in concentric rings around the 

 pith. (D.O.) 



LiNACEiE. — Litium. Link, H. Gr. Elementa Phil. Bot. 1837, tab. ii. 

 — Eeissek, S. Die Fasergewebe des Leines, &c. Ext. Denkschf. 

 K. Ak. Wiss. Wien. vi. with plates. An account of the develop- 

 ment and structure of the bast-cells. 



Steeculiace^i;. — Adansonia. "Walpers, G. Ueber Adansonia digi- 

 tata. Bot. Zeit. 1852, 295. Description of wood structure and 

 especially of liber. — Boinhax pentandra. Schleiden. Wiegman's 

 Arch. 1839, pt. 3. A. N. H. iv. 245. Wood almost entirely of 

 parenchyma, spiral annular and reticulated vessels,with rarely pro- 

 senchyma in exterior part of annual rings. — Delahechea rupestris. 

 The wood, of which an imperfect specimen is in the Kew Museum, 

 presents zones at unequal intervals of large tubular cavities, the 

 greater diameter of which is radial. These a2)pear to result from 

 the decay or resorption of enormous cords of delicately thin- 

 walled cells. The firmer portions of the wood consist of tliin- 

 walled parenchyma through which are scattered, between the 



