The surface of the hypostoma is so finely and obscurely granulated that it seems to be almost smooth. It is in the shallow groove above the lamellar tongueshaped posterior border that the elongated tubercular macula are situated. They are prominent and in horizontal sections they have a surface mottled by irregular black and white specks, the whole surrounded by a white border, [fig. 6]. This border and the other surface is pierced by series of parallel slitlike pores, [fig. 7], a feature peculiar to this genus. The vertical sections indicate a chain of indistinct prisms with a black, rounded central hollow between thick strata of clear whitish shell substance, [figs. 8, 9]. The shell substance on the sides is pierced by the straight, black tubes.
The cephalic eyes have the prisms indistinctly developed or badly preserved with a diameter of 0,04 millim. and height of 0,07 millim. In Encr. lævis the prisms are more distinct and larger with a diameter of 0,00 millim. ([pl. IV figs. 10-11]).
The maculæ are well developed, ovate, in E. lævis and obtusus and in the same position as in E. punctatus.
Griffithides Portlock.
The hypostoma of Griff. globiceps Phill. shows according to the figure given in H. Woodward's work pl. VI fig. 5 two somewhat obscure maculæ, but no mention is made of them in the description.
Harpes Goldf.
Harpes d'Orbignyanus Barr. Novák II Taf. I fig. 4, with small black maculæ. Harpes venulosus Corda. Novák II, Taf. I figs. 1, 2. Two narrow, horizontally placed maculæ.
Harpina Barr.
H. prima Barr. Novák II Taf. I fig. 5. Two maculæ in continuation of a narrow groove, at the base of the central globosity.