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.
Whoever can believe that the successes were numerous and that descriptions were given correctly - not only of facts present to the minds of inquirers, and of other persons present who were not consciously taking a share in the experiments, but also of facts necessarily unknown to all concerned - must of course be most impressed by the latter kind of success.
No woman makes any but the briefest appearance in his pages, though in reference to this it must of course be remembered that he was certainly a man past middle life when the events occurred, and perhaps a man approaching old age when he set them down.
Allowance must of course be made for the thickness of the wood.
