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similar, and camera sketches that I have made of the zooecia of the 
northern and of the Mediterranean one, show that here also there is 
hardly any difference ; both are without avicularia, and in neither is 
any ovicell known. However, the northern form has four to six 
lateral rosette plates, as shown by Levinsen,* whereas the papyrea 
from the Mediterranean has only two; again, F. carbasea has 
numerous small distal rosette plates, while F. papyrea has only one 
distal plate. These differences seem sufficient to justify us in separating 
the two, though I should have hesitated to do so on the grounds given 
by Kirchenpauer and Hincks. 
Both Kirchenpauer and Hincks make a strange mistake in saying 
that Smitt did not mention whether his papyrea was unilaminate, 
showing how unfortunate it is that Smitt’s valuable observations were 
not given to the world in a more universally read language, for in the 
Swedish text Smitt f refers to its being in the Carbasea form, but 
says that it does occur in the Flustra form. 
The creation of the var. Mazeli by Marion arises from Busk’s 
plates xlix. and 1. in the British Museum Catalogue being reversed, 
and Marion has not noticed that when Busk refers to plate 1. fig. 1, it 
should have been plate xlix. fig. 1. 
Flustra tenella Hincks, plate VII. figs. 24, 25 ; plate VIII. fig. 14. 
F. tenella Hincks, Ann. and Mag. Nat. Hist., ser. 5, xix. p. 313, 
pi. ix. fig. 1. F. securifrons Hincks, op. cit., xvii. p. 264. F. truncata 
Waters, Ann. and Mag. Nat. Hist., ser. 5, iii. p. 119. 
This in most particulars is so closely allied to F. securifrons that 
when first seen it was merely considered to be a variation. In both 
F. securifrons and F. tenella the branches are at the commencement 
very narrow, becoming rapidly wider, giving the wedge-shaped 
appearance to which Mr. Hincks alludes, nor are the fronds of 
F tenella always narrower than those of securifrons. The spines on 
which Hincks lays some stress are not constant. I have specimens 
from Naples on which I am unable to find any, nor are there any 
visible on the specimen from Rapallo ; on the other hand, in some 
Naples specimens they are very distinct, and also in a specimen from 
Roscoff, sent to me by Joliet as F. securifrons , they occur, but un- 
fortunately this specimen has neither avicularia nor ovicells. 
In the mandibles of securifrons the lucida is oval, whereas in 
tenella it is round (fig. 14). The ovicell is much shorter than that of 
securifrons , but the rib-like appendages to which Mr. Hincks alludes 
as occurring in securifrons are not constant, as I have a specimen 
from Karahavet without ; whereas in one from Nymundegab they are 
always present. The avicularia, though usually oblique, may be 
directed straight forward. / 
c * Danske Dyr., p. 50, pi. ii. fig. 38-46. 
t Smitt, Krit. Fort. ofy. Skand. Hafs-Bry., 1867, p. 380. 
