236 MARINE BIOLOGY OF THE SUDANESE RED SEA. 
Filisparsa Delvauri, Pergens, ‘‘Plioc. Bry. de Rhodes,” Ann. Nat. Hist. Hofmus. Wien, 
vol. il. (1887) p. 6; Bull. Soc. Belge de Géol. vol. iii. (1889) p. 64; Bull. Soc. Roy. Malac. 
de Belge, p. (2) & p. (6) (1889). 
? Idmonea gasparensis, MacG. Trans. Roy, Soc. Vict. vol. xxiii. p. 185, pl. 2. fig. 3. 
The specimen from Ras el Millan is only small and is partly covered by an 
encrusting foraminifer, but it shows the formation of the ovicell on the 
anterior surface very well. The end of the branch is clavate, and here the 
wall to cover the cell has just commenced to form, so that zocecia passing 
through the ovicell become funnel-shaped at the end—-that is to say, from 
each zocecium the finely perforated ovicell wall is commencing to grow, and 
will join the wall growing up from the base. It will be seen from the 
figure that there are a large number of zoccia in the ovicell. On the dorsal 
surface, near the ovicell, two or three zoccia are seen, at first suggesting 
Entalophora. 
The apertures of the zocecia are about 0°13 mm. 
Filisparsa, as illustrated by d’Orbigny, may include forms belonging to 
more than one genus ; but /. neocomiensis, d’Orb., may be taken as the type, 
with F. crassa doubtful. I* have previously alluded to the fact that the 
ovicell of Filésparsa is anterior, whereas in Jdmonea irregularis, Meneghini, 
the ovicell is dorsal. Perhaps the genus Yervia may be retained for that 
group, as Tervia folina, Jull., is the Jdmonea irregularis, Meneg. However, 
we stand on very uncertain ground regarding these genera until the ovicells 
of more species are definitely known. The dorsal position of the ovicell, 
which in this respect resembles Hornera, seems sufficient to remove such 
species from /dmonea, but of this we are not quite certain. From Zanzibar 
I have specimens in most respects like ZJdmonea irreqularis, with the ovicell 
anterior spreading for a considerable length among the zocecia, with the 
oceciostome curved over like the indraught funnel of a steamer. In 
considering the value of the position of the ovicell, we must not forget the 
extraordinary ovicells of Jdmonea Meneghini, Heller f, in which they take the 
place of one complete lateral series, showing what different forms the ovicells 
may take. 
Loe. Naples (W.) ; North Atlantic (B.) ; Holborn Island, Queensland, 
20 fath. (W.); Victoria ?; Ras el Millan, collected by Hartmeyer. 
Fossil. Rhodes ; Wola Lu’zanska (Hoe.). Mamah (Tert.). 
* Quart. Journ. Geol. Soc. vol. x]. (1884) p. 687. 
+ Waters, “ Ovicells of Cyclostomatous Bryozoa,’ Journ. Linn. Soc., Zool. vol. xx. (1888) 
p. 278, pl. 14. fig. 2. 
