QUESTIONS FOR SOLUTION 495 
by increasing complexity of structure ? How far do physical 
conditions alone effect similar changes in different plants ? 
How far do the curious facts of distribution among Arctic 
plants indicate an extended glacial climate ? Does the 
evidence from the migration and variation of temperate and 
subarctic plants indicate that this cold spell was world-wide, 
and was a factor in producing ' representative species ' now 
isolated from each other ? 
Without further quotation of detail here is enough to 
illustrate the range of Hooker's abounding help in matters of 
fact or of theory. Unfailing also is his information about 
books to be consulted or papers in scientific journals dealing 
with special points. Many were not procurable even from the 
Linnean Library, where Hooker arranged that Darwin could 
take out what volumes he wanted. Many he lent to his friend 
from his own botanical library to be studied and lightly marked 
on the margins for the purposes of his analysis, sometimes 
to be borrowed afresh that the marked passages might be 
consulted anew when some better scheme of analysis had 
presented itself or some flaw had been detected in the pre- 
vious scheme. * I never cease begging favours of you,' wTites 
Darwin in August 1855, when asking for the loan of the copy 
he had before of Asa Gray's Manual. 
The parcels generally go from Kew to the Nag's Head in 
the Borough, the headquarters of the Down carrier, whether 
botanical parcels or a ' magnificent and awful box of books,' 
though in the case of a rare orchid in flower, Parslow, the 
immemorial butler, would travel to Kew and carry it back in 
his own safe hands. 
Once, when Hooker had a fair copy of one of Darwin's 
MSS. to read, a misfortune happened which recalls, though 
it happily did not equal, the catastrophe to the sole MS. of 
Carlyle's ' French Revolution ' in J. S. Mill's house. The 
bundle ' by some screaming accident ' had got transferred to 
the drawer w^here Mrs. Hooker kept paper for the children to 
draw upon — and they ' of course had a drawing fit ever since.' 
Nearly a quarter of the MS. had vanished when Hooker pre- 
pared to read it at the end of a busy week. 
