366 NATURAL SCIENCE. 



JULY, 



foliage-leaves or shoots, which subsequently disappear in their turn, 

 and are replaced by others. When such axes or branch-systems he 

 horizontally or obliquely in the ground, and produce iateyal roots, they 

 are called rhizomes." — Text-book of Botany. 2nd Edition. English 

 translation, p. 216. 



Le Maout and Decaisne say : " The rhizome or root-stock is a stem 

 which extends obliquely or horizontally below or on the surface of 

 the ground, the advancing portion emitting fibrous roots, leaves, and 

 shoots, the posterior gradually dying." — Descriptive and Analytical 

 Botany. Hooker's translation, p. 11. 



Henfrey says : " The leaf-scaled stem, found especially among 

 herbaceous perennial plants, is seldom continuous with an axial 

 root. On the other hand, it is very prone to produce adventitious 

 roots, as is natural to its usually subterraneous or creeping mode of 

 growth." " If the main axis persists, producing a few branches each 

 year, and dying away behind but slowly, as it advances forwards, a 

 more or less root-like structure is produced, termed a root-stock or 

 rhizome." — Elementary Course of Botany, p. 25. 



We have here three definitions from works and authors of the 

 highest authority — one German, two Frenchmen, and one English- 

 man. I ask my opponents on what one point does our British 

 Stigmaria correspond to any of these three ? 



Let us examine Mr. Hick's arguments on this matter. 



External Character. — Even if no root is now to be found on the 

 earth on which the rootlets are arranged in quincuncial order, it does 

 not follow that such an arrangement could not formerly have occurred. 

 We have now no aerial Reptiles with wings twenty feet across, nor 

 archaic birds with their mouths full of true teeth ; but no one dreams 

 of advancing this as an argument against the former existence of the 

 Pterodactyle and the Hesperornis. I will therefore dismiss this argument 

 as valueless. 



Mr. Hick's next two arguments seem to me to neutralise one 

 another. In the first, the supposed rootlets cannot be rootlets 

 because in a specimen seen by Graf Solms, as these rootlets 

 approached the tip of the root, they bent towards its top, thus 

 approximating towards the condition of the leaves of a bud. In 

 the second he seizes upon Sir William Dawson's statement that the 

 rootlets radiate in all directions, hence they differ from those 

 "cowwo«/)/ met with in recent plants." What is or is not commonly 

 met with cannot be of much importance to an argument relating to the 

 Stigmarian question. I again leave these two opposite objections to 

 neutralise one another. 



Mr. Hick tells us that Stigmaria has two modes of branching, 

 one by dichotomy, and the other by the development of the lateral 

 appendages or rootlets in quincuncial order. I object to these 

 latter organs being designated branches. Morphologically, it is not 

 impossible that they may rather be regarded as highly developed and 



