Sentence Examples with the word asteroid

The position of the pores near the centre of the ambulacrals in Bothriocidaris need not be regarded as primitive, since other early Palaeozoic genera, not to mention the young of living forms, show that the podia originally passed out between the plates, and were only gradually surrounded by their substance; thus the original structure of the echinoid ambulacra differed from that of the early asteroid in the position of the radial vessels and nerves, which here lie beneath the plates instead of outside them.

Schiaparelli was primarily an observer-his first discovery was of the asteroid Hesperia in 1861-but he had also considerable mathematical gifts, as is shown in his treatment of orbital motions, published in 1864, and in other papers.