PHILIPPINE URTICACEAE. 477 
have been made under Kermula. The case is not covered by the list of nomina 
conservanda. — : 
3. LAPORTEA Gaudich. 
This genus contains the best-known and longest-remembered stinging 
plants of the Archipelago. This is especially true of LZ. meyeniana 
(Walp.) Warb., but other species appear even more virulent, and it is 
probable that all and certain that nearly all of our species cause extreme 
irritation. Valuable papers on this property of the genus have appeared 
in Australia ‘* and Paris,’* and the Philippine side of the case has been 
briefly stated by the writer.*° The stinging hairs are silicious, and at 
least in L. gigas contain formic and acetic acids; the effect being therefore 
both mechanical and poisonous. The latter is much the more pronounced 
as long as it continues, which may be from a few minutes to two or rarely 
more days, depending upon the severity of the case. Prompt relief may 
be had by the use of ammonia, carbonate of sodium, or probably any 
alkali: this was ascertained in Paris with LZ. moroides Wedd., and indepen- 
dently here with Z. meyeniana, The ordinary Philippine remedy is to 
apply to the injured surface the expressed sap from the inner bark of the 
same tree, and various sufferers have stated that it had given considerable 
relief. The experiments here gave negative results, but were not pro- 
longed beyond a few minutes, as it was obviously much less efficacious 
than soda or ammonia. However, the cell-walls continue to produce 
irritation rather than pain, especially on contact or immersion in water, 
often for three or four weeks; in one case supposed to have been due to L. 
mindanaensis for six or seven months. 
The systematic difficulties are very considerable, and the characters 
chiefly relied upon in the following key are drawn from pistillate plants, 
with which it has often been difficult to correlate staminate collections. 
All of our species fall within Weddell’s section Dendroenide, as limited by 
him, but there is a sharp distinction between those, such as L. meyentana, 
where the otherwise sessile flowers are borne upon a flabellate receptacle 
apparently formed by the union of their pedicels, and such cases as L. 
luzonensis where there is no such receptacle and the flowers are pedicelled. 
The separation of a new section would have been made in this paper, were 
the type of Dendrocnide known to me. All of our species seem to be 
endemic. ‘The oldest name for the genus is Urticastrum Fabr., but La- 
portea is maintained according to the decision of the Vienna Botanical 
Congress. 
Petrie, J. M. The stinging property of the giant nettle-tree. (Laportea 
gigas Wedd.). Proce. Linn. Soe. N. 8. Wales 31 (1906) 530-545, 
“Demilly, J. Les plantes du genre “Laportea” Gaudich., leurs caracteres, 
leur action urticante dangereuse, Bull. Sci. Pharmacol. 13 (1906) 144-149. 
% Robinson, C. B. Philippine contact-poisonous plants. Bull. Manila Med. Soc. 
2 (1910) 207-211. 
