8 
THE GEELONG NATTJRALIST. 
List," to insert this extreme northern species into the Dawson 
Eiver district column. "When in that district I paid especial 
attention to the Yellow-breasted Thickhead inhabiting the Brigalow 
(a species of acacia) scrubs where Dr. Eamsay's specimens came 
from, and could see no appreciable difference (except that it 
appeared a slightly smaller bird) between the species there found 
and the common Thickhead (P. gutfuralis) of elsewhere. How- 
ever I bow to Dr Eamsay's judgment in this matter, and by so 
doing save reducing by one the number of species in my egg 
collection. However, according to Dr Sharpe, I fear Mr Master's 
P. rohusta must sink as a synonym in favour of the Black-tailed 
Thickhead {P. melanurd). 
Mr Dudley Le Souef corroborates Dr Eamsay's statement 
about the very frail nest built by this variety. During a collect- 
ing trip to " Coomooboolaroo," September, 1893, -Mr Le Souef 
notes — " In a close bush we found the nest and egg of the Black- 
tailed thickhead {F. melanurd)^ but the structure was so slightly 
built that the egg was in danger of falling out." 
NOTES ON LECTUEE BY Me. H. T TISDALL, E.L.S., 
ON " MUCOE." 
Delivered before the Geelong Field Naturalists' Club, Oct. 11th, 
1895. 
Me. H. T. Tisdall, F.L.S., of Melbourne, delivered one of his 
popular and instructive lectures on Eriday evening, Oct. 11th. 
The subject chosen being " Mucor." There was a very large 
attendance of members and friends. The chair was occupied by 
Mr. a. H. Adcock, E.L.S. 
Mr. Tisdall, who is an honorary member of the Club, received a 
very hearty reception. 
The lecturer dealt with his subject in a most entertaining 
manner, keeping his hearers interested from the start of his- 
remarks to their close. The following heads being dwelt upon, and 
lucidly explained by Mr. Tisdall, by the aid of diagrams and 
drawings on the black-board. (1) Protococcus, a microscopic plant 
found in stagnant water ; (2) Spirogyra, also found in stagnant 
water ; (3) Bacteria, distributed everywhere as an invisible dust, 
both in air and water ; and 4, " Mucor," one of the common moulds 
to be found on damp bread, etc. The two methods of reproduction 
in " Mucor," were also described by the lecturer, namely: — 1st, 
The formation of the Spore ; and 2nd, — The formation of the 
Zygaspore. The different stages of reproduction were minutely 
described. 1st — How the upper end of an Aerial hypha swells. 
