' 
28 DR. J.D. HOOKER ON THE STRUCTURE AND 
number aïé extra-tropical; as Cynomorium, which attains lat. 41° N. in Europe; the two 
Mystropetala and Sarcophyte, which inhabit South Africa; Helosis guyanensis, which — 
extends to the La Plata district; and the North Indian species of Balanophora and Rho- — 
palocnemis. 1 
The genus Balanophora is confined to India, and the Malay and western Polynesian 1 
islands: it extends from the N.W. Himalaya at Simla throughout that mountain-range to 
the eastward, thence to the Khasia Mountains, Burma, and the Malay Peninsula, Sumatra, [ 
Java, the N.E. coast of New Holland, as far east as the New Hebrides; it is also found in | 
the Indian Peninsula, Ceylon, and the Philippine Islands, and no doubt occurs in Borneo — 
and New Guinea. The Helosideæ, with the exception of the Indian Rhopalocnemis, are 1 
confined to the American continent and islands, where they extend from Jamaica and | 
Mexico to the Pampas. Of the Langsdorfie, two species are American, and one (Thon- — 
ningia) is found on the west coast of tropical Africa. The Lophophyteæ, as far as is | 
known, all inhabit tropical South America, and are chiefly confined to South Brazil, Peru, - 
and New Grenada. 
The individual species of this Order have often exceedingly wide ranges, though some 
are extremely local. The most conspicuous examples of extensive distribution are: Cyno- 
morium coccineum, which ranges from the Canary Islands to the mouths of the N ile, viz. 
through 3000 miles of longitude ; Rhopalocnemis is found in lat. 27° N. in East Nepal and 
Sikkim, in the Khasia Mountains of East Bengal, and in Java, under the Equator, places 
no less than 3000 miles apart; Balanophora dioica, which has probably a still wider 
range; and B. fungosa, which is found both in East Australia and Tanna, places separated 
by 1500 miles of ocean. In the new world, Langsdorffia hypogea has been found in the | 
province of Oaxaca in Mexico, lat. 18° N., by Prof. Liebmann, in thé mountains of New 
Grenada by Mr. Purdie, at Rio de Janeiro by many collectors, and in the Pampas by 
Mr. Miers (lat. 84^ 8.) ; having thus a range of 52 degrees of latitude, and 4000 miles in 
a straight line. 1 
I do not find that the widely distributed species vary much according to the distance 
they spread; specimens from the most distant localities often being absolutely identical 
and all being very constant to one form : on the other hand, some of the most local species - 
as well as some of the most widely spread are excessively variable. As a general rule, 
the most imperfect forms vary most in general characters, especially Balanophora, th 
individual species of which differ in the size of their parts, in the form of their scales, their 
rhizome and their capitula, in the capitula being unisexual or bisexual, and in the size, 
form and number of the parts of the flower. Helosideæ again vary extremely in size an 
habit, but much less in the capitulum. Langsdorffie are rather variable, and Cynomo- 
rum 18 conspicuously so. , 
