254 VINE : NOTES ON POLYZOA FROM THE CORN BRASH OF THRAPSTON. 
Localities : Inferior Oolite, Longwy (Terquern) ; Cornbrash, 
Thrapston, Northamptonshire. 
Genus Proboscina. 
1826. Proboscina, Audouin, 1838 : Criserpia, Edwards, 1847 ; 
Idmonea, d'Orbigny, 1852 ; Proboscina, d'Orbigny. 
Palseont. Francaise, vol. v., p. 844. 
The species of this genus may be regarded as so many passage 
forms, which conveniently link together uniserial Stomatopora on the 
one side, and Diastopora on the other. By many modern workers on 
the Polyzoa group the genus is disallowed. Mr. George Busk in the 
III. British Mus. Catalogue (1875), and Mr. Hincks in the British 
Marine Polyzoa (1880), unite under one head, uniserial and multi- 
serial forms. Neither Mr. A. W. Waters, in his various papers on 
Australian Fossil " Bryozoa," nor Dr. Pergens, in his revision of 
d'Orbigny's Cretaceous " Bryozoa," make any distinction in the 
grouping of the forms generally characterised as Stomatopora and 
Proboscina. The use, however, of the two generic names has its 
advantages, especially when dealing with Jurassic species, and for its 
adoption I make no further apology. Mons. d'Orbigny, in the 
Pataeontologie Francaise, vol. v., Terr. Cret., pp. 844-147, has given a 
very full diagnosis of this genus, one of the distinguishing features of 
which is that species which are referred to the Proboscina group, 
commence their zoarial growth from an " egg-cell " (cellule ceuf). 
The Rev. T. Hincks, in his history of " British Marine Polyzoa " 
(1880), remarks (p. 425) that " Stomatopora is distinguished by its 
linear, adpressed, dichotomously branched Zoarium, in which the 
cells are generally immersed for a great portion of their length, and 
are not divergent, except in a very slight degree, and then almost 
exclusively towards the very extremity of the branches. The most 
marked variation within the limits of the genus is found in the forms 
which have the Zoarium partially free and erect. They constitute 
the sub-genus Proboscina of Smitt." The type species of the sub- 
genus, however, both of Smitt and Hincks' Stomatopora incrassata, 
Smitt (Brit. Mar. Polyzoa, pi. 59. fig. 2) differs from the ordinary 
Proboscina species found in the Cornbrash rocks. A much better 
idea of the group can be obtained by a careful study of the figure 
