CACTACEOUS GENERA. 51 



Miller, at almost the same time, in preparing a new edition of 

 his Dictionary restored two more of the pre-Linnsean genera, 

 setting forth in that rank, Cereus, Opuntia, Peireskia and Melo- 

 cactus, but to this last he assigned the Linnsean synonym of 

 Cactus ; perhaps wishing to conciliate, by a mere name, the pop- 

 ular botanist whose system of cactaceous plants he had so 

 boldly reyised. 



Some twenty years or more after Miller's restoration of the 

 old genera, Necker went over the ground in his own peculiar 

 fashion, reaffirming that in the Cactus of Linnaeus there are 

 four distinct genera ; and there is reason to think that this was 

 an independent proposition of his own, not suggested by Miller, 

 whose Gardener's Dictionary he may not have seen. At all 

 events, to three of his four proposed genera of cactaceous plants 

 he assigns names so entirely new and strange, that they can not 

 be identiiied at a glance and by name with the old genera, and a 

 critical study of his diagnoses becomes necessary to the deter- 

 mination of his types. 



Comparing his descriptions one with another, we ascertain 

 readily that the author subscribes to an opinion, even then anti- 

 quated, that only the globose and cylindric species of cacti have 

 stems, and that the compressed joints of such things as the 

 opuntise and phyllanthi are not branches but leaves ; so that, 

 while the globose and simple sorts are described by him as cau- 

 lescent, the kinds exhibiting any manner whatever of flattened 

 vegetative organs are classed as acaulescent, though the plants 

 be tall and large in certain cases. But in this error we find one 

 clew, and a sure one, to the identification of his cactaceous genera. 

 Another is given us in connection with the fruits ; for he de- 

 nominates a bacca the smooth soft-pulpy small-seeded fruit of 

 some, and as an achena that of those which as in Opuntia 

 have a firm fleshiness and contain larger and bony seeds. 



These few items of Neckerian cactaceous terminology are 

 enough to enable one to determine with certainty the identity 

 of each of his four genera Cactus, Cirinosum, Carpophillus and 

 Phyllanthus. 



Cactus, Neck. Blem. ii, 83. Of this he describes the fruit 

 as being an "olive-shaped many-seeded berry." The only Lin- 



