112 DR. T. ANDERSON ON THE ACANTHACEJE 
was able to devote some time to the examination of the Acan- 
thacec existing in Linneus’s Herbarium, now the property of the 
: Linnean Society. As the Acanthacee are eminently tropical, 
comparatively few species of the order were known to botanists 
of the time of Linneus. Consequently the limits of the genera 
of the order were very indefinite—so much so, that many of the 
old genera are coextensive with the tribes or subtribes I have 
adopted in the rearrangement of the order. Indeed, the old 
genus Ruellia is equivalent to my Suborder Ruellidee. Only five 
genera of 4canthacee are described in the 4th edition of the 
* Genera Plantarum,' published in 1752, and, with the exception 
of T'hunbergia, a genus of later date than 1752, these are the only 
genera recognized in Linneus’s Herbarium. The number of spe- 
cies is 67, distributed among the genera as follows:—Thun- 
bergia 1, Ruellia 18, Barleria 9, Acanthus 11, Justicia 26, Dian- 
thera 2. ` 
There are, among these 67 species, representatives of 28 genera, 
according to the views I entertain of the limits of genera in this 
order ; and many more, as will appear from the synonymy, if Nees 
von Esenbeck's opinions are adopted as he has stated them in 
the 11th volume of the * Prodromus.’ 
The following list includes all the species referred to genera of 
Acanthacee by Linnæus, and specimens of which exist in his Her- 
barium. In preparing it for comparison, I have taken the names 
appended to the specimens by Linnæus as the basis of the arrange- 
ment, but in the sequence of the genera I have adopted my own 
arrangement. In the case of the Linnean names, I have quoted 
the work in which the species was first described. The name I 
adopt is then given. 
A considerable array of synonymy occurs with some of the 
species ; this is rendered necessary by my having quoted all those 
species of Nees von Esenbeck which I consider identical. 
THUNBERGIA, Linn. fil. 
1. T. Capensis, Thunb. Nov. Plant. Gen. p. 21. T. Capensis, N. ab E. 
in DC. Prodr. xi. p. 55, et mihii—This plant bears the name of So- 
landra Capensis in Linnzus's Herbarium. 
RUELLIA, Linn. 
1. R. BLECHUM, Linn. in Ameen. Acad. v. p. 400. Blechum Brownet, 
Juss. Ann. du Mus. ix. p. 270; N. ab E. 1. c. p. 466, et mihi.—I refer 
Nees von Esenbeck’s B. Trinitense and B. Haenkei to this species: 
