SULCOCATA. 
211 
SULCOCAVA, cl’OrbigiiY, 1854. 
Syxoxyat. 
Laterocava, d’Orbigny, 1854. 
Diagnosis. 
Iclmoniidce with erect branched zoariiim. Branches laterally 
compressed. Zooecia opening in alternate transverse rows on 
the sides of the branches. The rows are uniserial. 
There is a considerable development of lamellar epitheca ; tear- 
shaped depressions in the epitheca are often present, and look 
like secondary apeitures. 
Type Species. 
Sulcocava cristata, 1853-4. Senonian : France. 
Afpixities. 
This genus has been veiy differently interpreted, owing to the 
depressions below the apertures. D’Orbigny placed the genus in 
the Cavida? ; iMarsson included it in the Entalophorida), in which 
it was doubtfully retained by Pergens. The best figures of the 
structure of the genus we owe to Marsson, who shows that the 
zoarium consists of a central axis of zooecia, covered by a laminar 
epitheca, which is traversed by alternate rows of apertures. 
Sulcocava appears tlierefore to be one of the specialized Cretaceous 
forms of Idmonids. It agrees with that family in the characters of 
the zooecia, the lateral compression of the branches, the bare 
reverse face, and the occurrence of the apertures in alternate 
transverse rows. The genus may, in fact, be regarded as a 
Beticrisma, Avith a laminated epitheca, in which there may be 
a series of depressions simulating secondary apertures. 
1. Sulcocava cristata, d’Orbigny, 1853-4. 
Syxoxymy. 
Sulcocava cristata^ d’Orbiguy, 1853-4. Bry. Cret. p. 1021, pi. 789, figs. 4-8,. 
,, ,, Pergens, 1890. Eevision, p. 368. 
,, „ Pergens, 1893. Bry. St. Pat. : Bull. Soc. beige Geol. 
vol. vi., Pr. Vb. p. 207. 
