We have not only the observations of Semper and Morse, but the anatomical investigations of King, to confirm the sliding action or lateral divarication of the valves of Lingula.
Trochosphaeraceae; female footless; subspherical, the corona bulging into a hemisphere which may equal the hemispherical body; anus apical; male as in Melicertaceae, Trochosphaere Semper (fig.
In recognition thereof the Genoese senate caused the words Civitas Calvi semper fidelis to be carved on the chief gate of the city, which still preserves the inscription.
The councils were also quoted, and especially that of Nicaea, which does not itself mention the question, but certain texts of which contained the famous gloss: Ecclesia romana semper habuit primatum.
Karl Semper has shown that these slugs have, in addition to the usual pair of cephalic eyes, a number of eyes developed upon the dorsal integument.