i76 HERAPATH, ON THE 
bling one of those of Echinus miliaris, one of our commonest 
Echini.* 
The collection and investigation of these pedicellariz has 
been a work of considerable time, having occupied the au- 
thor during the leisure moments of several years; these re- 
searches were in progress at the time of the discovery of the 
so called Atlantic mammalian jaw, but their publication has 
been delayed from various causes, the principal being the 
difficulties attendant upon making the photographs, and the 
extensive nature of the inquiry necessitating the making of 
numerous preparations of a delicate character from animals 
difficult to obtain. 
With regard to the probable nature of the pedicellarie, a 
growing feeling has arisen amongst naturalists that they are 
organs peculiar to the animals upon which they are found, and 
that, like the bird’s-head processes on the polyzoon, they were 
organs of defence or prehension, which, although not abso- 
lutely necessary to the existence of the Echinoderm, were yet 
as peculiar and special to the genus, and even indicative of 
the species, as the form of a tooth or the character ofa bone. 
It will be seen from these numerous photographs that these 
views were well supported by examples, and that whilst great 
general resemblance in form may be traced to the pedi- 
cellarize of the various species comprising the genus Echinus, 
yet there are many which are capable of recognition as being 
indicative of the species, and totally different from those of 
the genus Amphidetus, Spatangus, or Uraster, with which 
they may be compared, so that the author has no hesitation 
in stating that, in the same way that one animal may be 
recognised by its tooth, or an Kchinus by its spine, it would 
be equally possible to assert positively that a certain pedi- 
cellaria belonged to Uraster glacialis, to Echinus sphera, 
or to Amphidetus communis. Further, that although the 
general form of pedicellariz of Uraster rubens present great 
similarity to those of U. glacials, and those of Echinus 
miliaris agree remarkably in character with those of Echinus 
hvidus or Echinus sphera, yet there are abundant differences 
and peculiarities in their appearance to indicate to the 
practical eye to what particular species it may belong. 
The author has hitherto only found pedicellarize in the 
genera Uraster, Spatangus, Amphidetus, and Echinus, having 
examined many other genera of Echinodermata for them in- 
effectually, more especially Comatula, Ophiocoma, and Ophiu- 
ride. 
* It is much more like the pedicellaria of Cidaris palpilata, as it wants 
the long terminal tooth of Mdiaris (March, 1865). 
