Mr. Bentuam’s Review of the Order of Hydrophyllee. 271 
tinue to line the capsule without adhering to it, forming, as it were, an inner 
capsule, and at complete maturity dry up into a thin membrane. In Eutoca, 
Phacelia, and Emmenanthe they are converted into spurious dissepiments, 
which in some species meet in the centre so as to divide the capsule into two 
cells, and in Emmenanthe are, moreover, considerably dilated in the centre. 
In Zutoca Mexicana the adhesion with the parietes breaks off, and the fruit 
assumes the appearance of an unilocular polyspermous capsule with two cen- 
tral placentz. The same thing appears to take place in Phacelia fimbriata, 
but I have not seen any capsule in a state far enough advanced to be certain 
of the fact. 
The form of the capsule, ovoid or globose in most Hydrophyllee, is oblong- 
linear and compressed in Emmenanthe. 
The number of ovulze appears to have been the character chiefly relied upon 
in the formation of the genus Eutoca, and is, indeed, the only one which 
separates it from Phacelia, there being two only to each placenta in Phacelia, 
and often a great number! in Eutoca. ‘This character, however, is very uncer- 
tain, and forms very unnatural groups, whether we draw the line at 2, 4, 6, or 
8 to each placenta, or between the definite number, arranged in two rows on 
the one side, and the indefinite number, without apparent arrangement, on the 
other. The same character also, if applied to Nemophila, would dissever XV. in- 
signis from N. phacelioides, and N. pedunculata from N. parviflora, 
The seeds of all the Hydrophyllew I have been able to examine appear to be 
the same as those of Eufoca described by Mr. Brown in the above-quoted 
Appendix to Franklin's Voyage. 
From the above observations, and the characters of the six genera of which 
Hydrophyllee are now composed, it would appear that Hydrophyllum is a very 
natural genus, though difficult to characterize. Nemophila and Ellisia, when 
taken together, are a natural group, but are separated by a purely artificial 
character, and the same thing may be said of Eutoca and Phacelia. Emme- 
nanthe consists of but one species, so peculiar in its appearance and several 
characters that it will probably always remain distinct and well marked. 
I now proceed to a short synopsis of the genera and species of which the 
order consists. 
