402 M. Lestiboudois on the Vessels of the Latex, 



excellently with the rule in the section of the Polychaetse, and 

 would form an exception if we referred the Capitellacece to the 

 Oligochsetse ; this applies also to the absence of the vascular 

 system, and to the form of the bristles and their insertion in 

 ridges. 



With regard to the distinctions between Dasybranchus and 

 Notomastus indicated by Sars'in addition to the occurrence and 

 want of branchiae, I will only remark that, in well-preserved 

 small spirit specimens of Dasybranchus caducus, the two-ringed 

 nature of the segments is very distinct, and the proboscis of 

 such a specimen appears not so much scaly as covered with 

 papillse. 



XLIII. — Remarks on the Vessels of the Latex, the Vasa propria, 

 and the Receptacles of the elaborated Juices of Plants. By 

 M. Lestiboudois*. 



The older botanists looked upon the coloured fluids in vegetable 

 organisms as peculiar to certain plants, and called them " proper 

 juices/' The vessels containing these juices they, moreover, 

 named " proper vessels," and the plants in which such secretions 

 were recognized, laticiferous or lactescent plants. 



Besides coloured liquids, other juices, of a completely distinct 

 character, occur in plants, such as gum, resin, oil, &c. Grew 

 termed the receptacles of resinous fluid in the Coniferse " tur- 

 pentine-vessels," and those that contained a milky or white fluid 

 " milk-vessels." Linck designated all such organs by the name 

 of " reservoirs of special secretion." Mirbel gave the title of 

 " proper vessels " to all receptacles of special secretion, whether 

 milky, resinous, or oily, calling those "solitary" which were 

 scattered throughout the tissues, and those " fascicular " which 

 were aggregated together. In this latter category he placed the 

 textile fibres of Asclepias, of Hemp, &c, although such struc- 

 tures were destitute of laticiferous juices and were, in fact, 

 nothing more than the cortical fibres of those plants. 



DeCandolle, whilst recognizing the heterogeneous nature of 

 special secretions, at first regarded them as the nutritive juices 

 of the plants, but subsequently abandoned this opinion (Organo- 

 graphie, 1827), and ranged all coloured fluids among secreted 

 products, or those prepared by vesicular glands, and thus esta- 

 blished a distinction between them and the juices occupying the 

 lacunas of the cellular tissue. These latter cavities he agreed 

 with Linck in calling u reservoirs of proper secretion." In his 

 ' Physiologie vegetale/ published afterwards in 1832, although 



* Translated by Dr. Arlidge from the ' Comptes Rendus ' for March 1863. 



