52 NATURAL HISTORY MISCELLANY. 
and Dohrn has adduced the supposed zoéa-form larva of these egg- 
parasites as a proof, we cannot but think in a subject so purely 
speculative as the ancestry of animals, that the facts brought out 
by Ganin tend to confirm the reviewer’s theory, expressed in the 
last number of this journal, that the ancestry of all the insects 
(including the Arachnids and Myriapods) should be traced directly 
to the worms. The development of the degraded, aberrant arach- 
nidan Pentastomum accords, in some important respects, with that 
of the intestinal worms. The Leptus-form larva of Julus, with its 
strange embryological development, in some respects so like that 
of some worms, points in that direction, as certainly as does the 
embryological development of the egg-parasite Ophioneurus. The 
Nauplius form of the embryo or larva of all Crustacea, also points 
` back to the worms as their ancestors, the divergence having per- 
haps originated in the Rotatoria. In these similar modes of devel- 
opment between the worms and the Crustacea on the one hand, , 
and the worms and insects on the other, have we not a strong 
genetic bond uniting these three great classes into one grand sub- 
kingdom; and can we not in imagination perceive the successive 
steps by which the Creator, acting through the secondary laws of 
evolution, has built up the great articulate division of the animal 4 
kingdom ?— A. S. P. E 
NATURAL HISTORY MISCELLANY. 
BOTANY. 
TRANSPIRATION OF AQUEOUS VAPOR BY THE LEAVES OF PLANTS: 
— Professor McNab of Cirencester College, England, has recently 
published an important series of experiments on this subject. 
The plant experimented on was in all cases the common cherry- 
ouh under the following heads :—1, Quantity of water in the 
yos, The mean of several experiments gave 63.4 per cent. 2. 
Quantity of water which can be removed by calcium chloride, of 
