334 Bibliographical Notices. 
I have already pointed out the many and important differ- 
ences which there are between the two forms. A comparison 
of MacGillivray’s figure with my own will show that they are 
more or less dissimilar in almost every element of the struc- 
ture. It is not the mere number of the spines which is 
different ; the difference in character is much more important. 
MacGillivray’s description, ‘long, slender, incurved spines,” 
does not apply to those of B. distans. Their form and 
arrangement, as shown in his figure, offer a complete contrast 
to those of the present species *. 
It is unnecessary that I should repeat here the careful 
comparison of the two forms which is embodied in the 
original account of B. distans; but I may emphasize the 
differences in the avicularia, of which enlarged figures are 
given. 
‘Annals,’ Feb. 1882 (p. 80 sep.). 
Membranipora pilosa, Linn., form multispinata. 
This form was referred doubtfully to JZ. pilosa, but I now 
regard it as a distinct species which will rank as JZ. multi- 
sptnata (see the original description, doc. czt. and the figure on 
plate v.). 
{To be continued. | 
BIBLIOGRAPHICAL NOTICES. 
Catalogue of the Type Fossils in the Woodwardian Museum, Cam- 
bridge. By Henry Woops, B.A., F.G.S. With a Preface by 
T. McKenny Hucues, M.A., F.R.S. 8vo. 189 pp. Cambridge, 
1891. 
To enable biologists to be within their rights, and not to infringe 
on those of others, in giving original names to new genera of 
animals and plants, there have been provided published lists (and 
very lengthy catalogues they are) of the appellations already appro- 
priated ; and lists of specific names are available to a limited extent ; 
but still the recorder of a new species has to be assured whether or 
no his specimens differ from or agree with already published forms ; 
and to this end it is requisite that he should see those that have 
been already described, the published figures and descriptions not 
being always satisfactory. 
* ¢Polyzoa of Victoria,’ decade v. p. 82, pl. xlvi. figs. 3. 
