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Updated: May 5, 2025
There is often a primitive and negroid character about dwellings of formidable personages, heads placed on stakes adorn their exterior, or shields are ranged round the walls. The provinces are ruled by removable earls appointed by the king, often his own kinsmen, sometimes the heads of old ruling families. The "hundreds" make up the province or subkingdom.
Although not more than half a dozen out of the million or more species in this subkingdom have thus been brought to the uses of civilization, the forms are interesting not only for what they give, but for the promise of further contributions when this great problem of winning help from the insect world receives adequate consideration.
All forms of animal life, from the coelenterates to the mammals, follow the same path in their embryological development as far as the gastrula stage, but here their paths widely diverge, those of each subkingdom going their own separate ways. We may infer, therefore, that during the pre-Cambrian periods organic evolution followed the lines thus dimly traced.
ECHINODERMS. This subkingdom comprises at present such familiar forms as the crinoid, the starfish, and the sea urchin. The structure of echinoderms is radiate. Their integument is hardened with plates or particles of carbonate of lime.
Each of these early embryological stages is represented by living animals, the undivided cell by the PROTOZOA, the blastosphere by some rare forms, and the gastrula in the essential structure of the COELENTERATES, the subkingdom to which the fresh-water hydra and the corals belong.
COELENTERATES. This subkingdom includes two classes of interest to the geologist, the HYDROZOA, such as the fresh-water hydra and the jellyfish, and the CORALS. Both classes existed in the Cambrian. The Hydrozoa were represented not only by jellyfish but also by the GRAPTOLITE, which takes its name from a fancied resemblance of some of its forms to a quill pen.
Accepting, then, the type of articulates as founded in nature from the similar modes of development and points of structure perceived between the worms and the crustacea on the one hand, and the worms and insects on the other, have we not a strong genetic bond uniting these three great groups into one grand subkingdom, and can we not in imagination perceive the successive steps by which the Creator, acting through the laws of evolution, has built up the great articulate division of the animal kingdom?
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