Linnaan Society. 41 



unpublished, made by himself on the larvae of Clissocampa Neustria, 

 in July 1837. 



April 5, 1853. — R. Brown, Esq., President, in the Chair. 



Read a " Note on the Nature of Fasciated Stems." By the Rev. 

 William Hincks, F.L.S., Professor of Natural History in Queen's 

 College, Cork. 



The author lays it down as an indubitable principle, that what we 

 call monstrosities or anomalies, either in the animal or vegetable 

 kingdom, are always susceptible of explanation from the operation, 

 under unusual circumstances, of causes or principles the ordinary 

 operation of which produces the normal structure of the species. 

 Hence they are always worth studying until a satisfactory explana- 

 tion of their nature has been arrived at, and even when that is ac- 

 complished they have still an interest as illustrations of principles 

 which we apply in the explanation of normal structures, or as proofs 

 of the truth of particular views in respect to the origin or relations 

 of parts in certain tribes. In accordance with this view of the im- 

 portance of such investigations he proceeds to the consideration of 

 the nature of fasciated stems, which, in concurrence with the view 

 taken by Linnaeus in his ' Philosophia Botanica,' he is disposed to 

 regard as formed by a group of coherent stems. According to this 

 view the real peculiarity would consist in the number and remark- 

 able arrangement of the buds, the coherence of stems brought to- 

 gether in such a relative position being, as shown by innumerable 

 examples, a matter of course. Having regard to the crowded or 

 unusually placed buds which are found in the anomaly called 

 plica, tracing this cohesion upwards from the not uncommon ad- 

 herence of two stems, and observing what must necessarily happen 

 from numerous branches occurring together, it seems to him that the 

 fascia is by no means difficult of comprehension. The striae which 

 it almost invariably presents exhibit the traces of the lines of junc- 

 tion ; and the curved or spiral contraction, which is so often met 

 with, is perhaps accounted for by the growth in connexion with each 

 other of internodes of unequal length. He would not, however, affirm 

 that every stem which is called fasciate is composite in its nature ; 

 for that term has been extended to cases of riband-like expansion, 

 which, although dependent also on excess of nourishment, are dis- 

 tortions of a single stem . 



Mr. Hincks then refers to the objections taken to the theory of 

 Linnaeus by several recent physiologists, and most clearly and ex- 

 plicitly stated by M. Moquin Tandon in his ' Teratologic Vegetale ' 

 under the following heads : — 1. " We find plants with a single stem 

 fasciated (as Androsace maxima), and nothing announces to us that 

 we have in this case several individuals united together." 2. " On 

 certain fasciated stems we may remark that the branches are of the 

 same number and the same arrangement as in the normal condition." 

 3. *' Two branches accidentally united in the direction of their length 

 form a body of which the transverse section presents a figure more 

 or less resembling a figure of 8, if the coherence is recent or slight, 



