266 THE ZOOLOGIST. 
a comparison of the parts in the Batrachia, and of the sacral region in 
certain groups of the birds, and, in a somewhat technical summary, state 
their belief that, although often very puzzling and complicated from 
occasional variations in species and otherwise, the true sacral vertebre 
may be defined in all Vertebrates above fishes where hind limbs are well 
developed. 
A contribution on Corals, viz. “ Notes on the genus Alveolites (Lamarck) 
and on some Allied Forms of Paleozoic Corals,” by Prof. H. Alleyne 
Nicholson and Mr. Robert Etheridge, Jun., in the absence of those gentle- 
men, was read by the Secretary. It seems, according to these authors’ 
researches, that the name <Al/veolites covers a multitude of forms which are 
not always united by relations of genuine affinity; even definition of the 
so-called type-forms are subject to different interpretations. To clear diffi- 
culties examination of a large series has been instituted, and microscopic 
sections, whenever available, have been made and carefully compared. 
Discussing the characters and attributes of the genus, and placing the 
question in its historical aspect, they proceed by taking the affinities of the 
several species in groups :— 
Group A.—Alveolites suborbicularis (Lamarck), along with which may be 
placed A. compressa (Edw. & Ham.), A. Labechei (E. & H.), and A. Grayi 
(E. & H.); these agreeing, however, in many respects with the genus 
Fawvosites. 
Group B.—Cemites (Eichwald): not easily separated from the foregoing. 
Group C.—Brachypora (Lindstrém), The A. Fischeri(Bill.) and A.fron- 
dosa are referable to this genus. 
Group D.—Alveolites septosa (Fleming), with which they add Chetites 
radians (Fisch.) and A. depressa (F lem.) as natural allies. 
Group E.—Chetites (Fisch.), with Monticulipora (D’Orb.) and Stenopora 
(Lonsd.), have much in common with Alveolites anil Favosites. 
Group F.—Alveolites Goldfussi (Bill.), with which A. Remeri is allied, 
comes near 4. Tongti (EK. & H.), which latter Lindstrom puts with Favosites ; 
but further investigation is necessary as to these latter. 
Mr. Alfred W. Bennett exhibited and made remarks on some specimens 
of abnormal primroses; and Mr. G. S. Boulger read a short paper on the 
perfoliate pennycress (Thlaspi perfoliatum).—J ames Murte. 
ZooLoeicaL Society or Lonpon. 
April 17, 1877.—Osperr Savin, Esq., F.R.S., in the chair. 
The Secretary read a report on the additions that had been made to 
the Society’s Menagerie during the month of March, and called particular 
attention to a collection of rare Himalayan Passeres, purchased March 8th, 
