Thiselton-Dyer . — Morphological Notes . 751 
Loranthus in copious fruit in the North Gallery at Kew (No. 
23). Unfortunately, as with so many other studies of vegeta- 
tion by the accomplished artist, it is hung too high for proper 
examination. 
Fig. 2 represents the appearance of the Cereus stem after the 
dissection described above. ' The epidermis and hypoderma 
have been removed, carrying with them the spiny armature 
and the external stems of the Loranthus . The cortical 
parenchyma and medullary tissues have been washed away, 
as well as any cortical fibro-vascular system which existed 1 . 
The fibro-vascular cylinder is perforated with slits, each of 
which corresponds to one of the external f spine-cushions ’ 
on the surface of the stem. In general plan the resemblance 
of the cylinder to that of a tree-fern is obvious. But the 
leaves corresponding to the slits are, as is well known, sup- 
pressed. And though De Bary 2 cites authorities for regard- 
ing the prickles of Cactaceae as ‘emergences,’ the view of 
Goebel 3 , that ‘ the spines are transformed leaves which arise 
upon very much reduced lateral shoots,’ is no doubt correct. 
Fig. 1 shows the short external branches of the Loranthus : 
they are a little longer than the spines, and perhaps derive 
some protection from them. 
In Fig. 2 the haustorium of the Loranthus is seen to consist 
of a very irregular mass freely ramifying and sometimes 
anastomosing in the cortex of the Cereus . The surface of this 
mass consists everywhere of a uniform tough and indurated 
tissue, yellow when fresh but pale brown when dried. The 
dissection at once furnished the clue to a very enigmatical 
object of unknown history which I found amongst the 
Cactaceae in the Kew Museum. It is a hollow body with 
a thin wall of an irregular shape branched in all directions, 
and gives the impression of having been blown out from some 
plastic material which has afterwards set hard. The greatest 
diameter of the hollow portion is some two inches, and the 
1 See De Bary, ‘ Comparative Anatomy of the Phanerogams and Ferns/ p. 310. 
2 Loc. cit., p. 66. 
3 Goebel, ‘Organography of Plants/ pp. 168, 169. 
