328 ON TUE NATURAL KOPES USED FOR PACKING 



included in the eighth volume of the ' Botanische ZeiUing,' by Her- 

 mann Criigei-, entitled " Einige Beitrage zur Kenntniss von sogenannt- 

 nen anonialen Holzbildungen des Pikotylenstammes," and published 

 in 1850. Notices of the structure of other Lianas are also to be met 

 with in isolated memoirs, some of which will be referred to, and in 

 most botanical text-books, particularly in those of Lindley, Schleiden, 

 Richard, and Duchartre. Much important information may also be 

 anticipated from some recent memoirs by a Brazilian botanist. Dr. 

 Ladislaii Netto, who has presented memoirs on the subject to the 

 French Academy, extracts only from wliich have been published in the 

 ' Comptes E,endus' and ' Annales des Sciences' for 1866, 1867, etc. 



Bignoniacece. — Travellers in the Brazils tell us that by far the larger 

 number of climbing plants in tlie South American tropics belong to 

 the Natural Ordei" Malplgliiace^e, and we should therefore expect that 

 this woidd be the family which furnishes tlie majority of natural ropes. 

 But this does not appear to be the case ; B'tgnonlacece being the most 

 largely used for supplying Lianas for packing purposes, both as regards 

 the quantity of ropes, and the largest number of species. 



Most of them are readily identified by the remarkable and symme- 

 trical outlines presented by the cortical and woody systems of their 

 stems when seen in a horizontal section, the bark being projected into 

 the woody tissue, towards the centre, in the form of rays. These cor- 

 tical rays are wholly formed of liber- fibres, and they vary in colour 

 according to the species. In the majority of stems such prolongations 

 of the bark are four in number, disposed after the manner of a Maltese 

 cross. In a few species each of the four cortical portions is very thick 

 and perfectly square in contour, but in the larger n*imber they are long 

 and slender, frequently reaching the pith itself. 



Tiie yearly additions to these rays do not proceed after a uniform 

 method, and I sliall notice two or three of the principal arrangements. 

 The more common is that where the four primitive rays are deeply 

 projected into the wootly portion, tlie additions taking place each sea- 

 son in the form of plates deposited on each side of the primitive cor- 

 tical ray. It is difhcult without the aid of a diagram to convey a clear 

 idea of the sequence in which the various portions of bark and wood 

 are formed ; suffice it to say that each successive addition of bark is 

 projected into the wood a shorter distance tiian its predecessor, and as 

 the innermost extremity of every plate is truncate or rectangular, it 



