Similar experience was adduced by the working of the state telegraphs in Switzerland and in France.
Good cytological evidence has been adduced in favor of both theories, but further investigation is necessary before any definite conclusion can be arrived at.
Chun and Woltereck, on the other hand, regard the stem as a stolo prolifer arising from the aboral pole, that is to say, from the ex-umbrella, similar to that which grows out from the ex-umbral surface of the embryo of the Narcomedusae and produces buds, a view which is certainly supported by the embryological evidence to be adduced shortly.
In support of this idea, independently of the ecclesiastical innovations, many significant facts could be adduced.
For the Heteronemertines arguments have been adduced to prove that here they have the physiological significance of a special respiratory apparatus for the central nervous tissue, which in all these forms is strongly charged with haemoglobin.