FILISPAESA. 
67 
Type Species. 
Filisparsa neocomiensis, d’Orbigny, 1853-4. Ery. Cret. p. 817, 
pi. 760, figs. 10-13. Xeocomian : Baudrecourt, France. 
Affinities. 
This unimportant genus may he regarded as a group of Proloscince 
\rith an erect habit. It is here retained solely on the ground of 
convenience ; for examination of the series of ‘ species ’ assigned 
to the genus shows that it includes representatives of the principal 
types of Prohoscina. Thus, Filisparsa neocomiensis, Orb., repre- 
sents the type of Prohoscina aUernata, d’Orb. ; Filisparsa ramosa, 
Orb., similarly represents the type of Prohoscina crassa (Bom.). 
It appears, therefore, probable that the group of Filisparsa had 
a polygenetic origin. But as there is no definite proof of this idea, 
the group may be retained simply on the score of convenience. 
For, if Filisparsa be abandoned, of the five Cretaceous species 
founded by d’Orbigny, no less than three (viz., F. crassa, 
F. alternata, and F. ramosa) would have to be renamed, and 
possibly also the other two {F. neocomiensis and F. reticulata). 
D’Orbigny placed Filisparsa in his family, the Sparsidae, which 
was far too comprehensive to be retained. But Filisparsa was 
placed close beside Stomatopora, Prohoscina, Berenicea, and 
Biastopora, in what seems to me its right position. Pergens has 
removed it to the Idmoniidae. But I do not see any character in 
his diagnosis of his Diastoporidae to exclude it from that group. 
By the irregular arrangement of its apertures, Filisparsa appears 
to belong to the same series as Prohoscina, and not to Idmonea 
or Crisina. 
Filisparsa reticulata, d’Orbigny. 
SrxoxTXY. 
Filisparsa reticulata, d’Orbigny, 1853-4. Bry. Cret. p. 820, pi. 757, figs. 1-4. 
,, ,, Pergens, 1890. Eevision, p. 351. 
,, cenomana, Canu, 1898. Bry. St. Cal. : Bull. Soc. geol. Fr. ser. 3, 
Yol. XXV. p. 743, pi. xxii. figs. 3, 4. 
Deygnosis. 
Zoarium reticulate ; formed of flattened branches. The reverse 
face is slightly convex. 
Apertures crowded; irregular in arrangement, but in places 
tending towards quincuncial. Peristomes well raised. 
