He held it against his arm and trotted through the hold, down stairwells until the familiar must of the underground slowed his step.
Since no graptolites are known living, or, indeed, since palaeozoic times, the interpretation of their structure and affinities must of necessity be extremely conjectural, and it is by no means certain that they are Hydrozoa at all.
With such an enormous geographical range the species must of necessity present itself under a considerable number of local phases, differing from one another to a greater or less degree in the matters of size and colouring.
Allowance must of course be made for his point of view, but less so perhaps than in the case of any other writer so intimately concerned.
So far as the results of criticism are still uncertain with regard to the age and authorship of any of these, Ewald's conclusions must of course be regarded as unsatisfactory.