280 : PROF. G. DICKIE ON ALG® 
different intensities on the upper and lower halves of aroot. But 
it must be looked at as qualitatively different from longitudinal 
growth, and dependent on different conditions for its completion. 
lt is only by accepting some such view as this, that we can attempt 
to understand the facts of the case, namely—that injury to the 
punctum does not seriously interfere with longitudinal growth, 
nor with geotropic growth if the stimulus of gravity has previously 
acted on the root when intact; whereas such injury does inter- 
fere with the process by which gravitation stimulates the root to 
subsequent curvature. Our view that the punctum is the part 
which receives the stimulus is, as a theory, consistent with the facts 
before us. But it is not the only possible theory ; and it would 
be also rational to content one's self with saying, that for some un- 
known reason the injury to the punctum has a special paralysing 
effect on the power which roots possess of receiving the stimulus 
of gravitation. 
Notes on Alge toy the Himalayas. 
By Dr. Gzonax Dıfkır, F.R.S., F.L.S. 
[Read May 4,1882.) 
Tuz materials which form the subject of this brief notice were 
collected by Dr. Watt during the months of May and June, 1881. 
His report is, that the collections were made from pools and lakes 
in the Upper Batong Valley, Sikkim, at 15,000 to 18,000 feet 
above sea-level ; I am not aware that any gatherings have been 
previously made at such altitudes anywhere. Unfortunately, the 
labels giving precise localities were accidentally destroyed : some 
were from moraine lakes at the Kanglanamo, and others from 
two moraine lakes in Prickchu Valley, between Kubra and 
Kinchinjunga. 
I am indebted to my friend, Rev. G. Davidson, Parish Minister 
of Logie Coldstone, in county of Aberdeen, for valuable aid in 
recording the Diatoms, and also to Herr Grunow, one of the 
highest authorities in that department; Mr. Roy, secretary to 
our Aberdeen Natural-History Society, examined and noted the 
Desmids. 
SIPHONACEZ. 
VAUCHERIA. Fragments only, and not sufficient for identifi- 
cation of the species ; their diameter equal to *001 of an inch. 
