. Bulletin of the British Museum (Natural History). 82 PITT AND TAYLOR FWW, 0-17-()-2() mm; GTL, c. 0-78 mm; GW, c. 0-34 mm; LOSM, c. 0 08 mm; TOSM, c. 010 mm; LOPM, c. 0 05 mm; TOPM, c. 0-06 mm. Remarks. This uncommon species differs from F. neocomien- sis d'Orbigny by having more closely-spaced apertures (see d'Orbigny 1853: pi. 760, figs 10-13), and lacking the distinct cresent-shaped growth lines depicted by d'Orbigny on branch reverse surfaces. However, a precise evaluation of the distinc- tions and relationships between the two species must await a modern revision of d'Orbigny'
. Bulletin of the British Museum (Natural History). 82 PITT AND TAYLOR FWW, 0-17-()-2() mm; GTL, c. 0-78 mm; GW, c. 0-34 mm; LOSM, c. 0 08 mm; TOSM, c. 010 mm; LOPM, c. 0 05 mm; TOPM, c. 0-06 mm. Remarks. This uncommon species differs from F. neocomien- sis d'Orbigny by having more closely-spaced apertures (see d'Orbigny 1853: pi. 760, figs 10-13), and lacking the distinct cresent-shaped growth lines depicted by d'Orbigny on branch reverse surfaces. However, a precise evaluation of the distinc- tions and relationships between the two species must await a modern revision of d'Orbigny's type specimens. Family MULTISPARSmAE Bassler, 1935 (= MACROECIIDAE Canu, 1918) Genus REPTOCLAUSA d'Orbigny, 1853 Type SPECIES. Reptoclausa neocomiensis d'Orbigny, 1853, by subsequent designation of Bassler, 1935; Valanginian of Ste Croix (Switzerland). Remarks. The type species of Reptoclausa has been revised by Hillmer (1971). The genus is distinguished by its character- istic colony form; colonies are sheet-like and have autozooecia located on ridges which form subcolonies separated by ex- panses of kenozooecia. Reptoclausa appears to be closely related to Idmonea (see below, p. 84). The autozooecial ridges may be homologous with the branches of the latter genus, and the kenozooecia equivalent to the kenozooecia which often form a selvedge on the flanks of the branches of Idmonea. Species of Reptoclausa differ from one another in the shapes and relationships of the autozooecial ridges. In R. neocomiensis the ridges arc short and taper both distally and proximally; new ridges arise from areas of kenozooecia and are not connected with established ridges. A similar arrange- ment occurs in R. hagenowi (see below), but the ridges are typically longer. Furthermore kenozooecia in R. hagenowi are extremely slender, whereas those of R. neocomiensis have hexagonal frontal walls only slightly smaller in area than the autozooecial frontal walls. A Jurassic species of Repto- clausa, R.
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