A Monograph on the Sub-class Cirripedia · Charles Darwin
CRYPTOPHIALUS MINUTUS.
Fig. 10, Lower enlarged end of œsophagus, where entering the stomach, viewed from one of the sides bearing the discs of teeth; _a_, upper cut off end of œsophagus; _b_, the lower end and natural opening; _c_, thickened rim, having a somewhat beaded structure. 11, The same; diagram giving a transverse section of the above in the line of the discs of teeth; _c c c c_, four thickened beaded edges; _e e_, two other but narrower and less prominent beaded edges; _d d_, discs of teeth; _f_, rows of fine bristles; the almost double row of bristles on each side under (_d_) is not of course seen in this section. 12, Lower end of œsophagus viewed from a position at right angles to that in fig. 10; or from the side _e_, of the diagram, fig. 11; the two discs of teeth are consequently shown in profile; _a_, upper cut off end of œsophagus; _b_, lower natural end; _c_, _c_, thickened edges; _e_, narrower thickened edge, projecting towards the beholder; _d_, disc of teeth seen in profile. 13, Portion of one of the cirri; _a_, lower segment of pedicel; _b_, upper segment, supporting the two rami. 14, Segments of one of the rami much enlarged; _a_, thickened shield-like portion of membrane. 15, Ovum, (thirty-five times the natural size.) 16, Egg-like larva in the first stage, on same scale. 17, " " in the second stage, on same scale. 18, Larva in the last or pupal stage, on four times the scale of fig. 15-17; _a_, antennæ; _b_, apodeme and eyes; _c_, abdominal bristles. A male would have been developed from this pupa. 19, Male on same scale as the pupa, fig. 18; _a_, three terminal segments of the antennæ of the pupa; _d_, orifice of the sack.
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