278 
SIPHON^IOTYPHLUS. 
Dimensions. 
"Width of branch 
Diameter of zocecia ... 
Diameter of aperture ... 
D. 2741. 
•8 mm. 
•12--18 „ 
•08--12 „ 
D. 2829. 
about 2 ram. 
• 12--2 „ 
•08--12 ,, 
Disteibution. 
England : 
Middle Chalk : Chatham. 
Chalk Detritus : Charing, Kent. 
? Upper Greensand: Cambridge {fide Vine). 
Foreign : 
Senonian — Campanian : Eiigen. 
Turonian : Strehlen, in Upper Planer. 
PiGUEES. 
PI. XII. Fig. 2. A narrow zoarium, X 10 dia. Middle Chalk: 
Chatham. Yine Coll. D. 2741. 
PI. XII. Fig. 5. A fragment of a wider zoarium, x 10 dia. 
Chalk Detritus : Charing. T. R. Jones Coll. D. 2829. 
Affinities. 
This species differs from S. plumatus by the less regular arrange- 
ment of the apertures and the absence of the selvage. 
LIST OF SPECIMEXS. 
D. 2829. A fragment of a zoarium (on slide). Chalk Detritus. Charing, 
Kent. T. E. Jones Coll. Figd. PI. XII. Fig. 5. 
D. 4478. A smaller fragment (on slide). Chalk Detritus. Charing. T. E. 
Jones Coll. 
D. 2741. A narrow specimen (on slide). Middle Chalk. Chatham. Yine 
Coll. Figd. PI. XII. Fig. 2. 
UXREPRESEXTED AXD DOUBTFUL SPECIES. 
1. johnstrupi (Pergens & Meunier), 1887. 
Stn. Bisidmonea johnstrupi, Pergens & Meunier, 1887. Bry. gar. Faxe : 
Ann. Soc. roy. mal. Beige, vol. xxi., Mem. 
p. 219, pi. xii. 
Char. — Of thick branches, sometimes ending above in a cylindrical branch. 
Apertures in pinnate rows of from three to nine. Superficial striations not 
apparent. 
Distrib. — Danian : Faxoe. 
