The President's Address. By Dr. H. Woodward. 139 



or seven pairs of pouch-like gills ; the mouth is circular, or semi- 

 circular and suctorial, but there are no jaws, and the teeth are 

 arranged around the buccal cavity. To this order belong the 

 " Lamprey " and the " Hag-fish." 



The " Lamprey " (Petromyzon) is marine, but ascends rivers to 

 spawn. 



The " Hag-fish " {Myxiiie) has similar habits. Its teeth are 

 numerous, minute and serrated ; it lives attached, parasitic, on 

 other fishes, and even in some instances enters their body-cavity. 



The species have a very wide geographical distribution in the 

 North Atlantic, the shores of Japan, Straits of Magellan, the North 

 Sea, Norwegian fiords, the British shores, and many of our rivers, 

 as the Thames, Severn, etc. 



The point of geological interest which they present to us is 

 that, although the rest of the animal-structure is soft, or merely 

 cartilaginous and incapable of conservation, their minute micro- 

 scopic teeth of glistening chitinous consistence may readily have 

 been preserved. 



Now certain minute bodies, like conical and serrated teeth, but 

 of considerable variety of form, were discovered by Pander in the 

 Silurian and Devonian rocks of Eussia, as long ago as 1856, and in 

 1875 by Prof. Newberry in North America ; in 1879, they were 

 obtained by Dr. G. J. Hinde, P.E.S., in the Cambrian and Silurian 

 rocks of Britain, North America, and of Sweden ; and later, both 

 Prof. Newberry in America, and Prof. Pander in Eussia, have ex- 

 pressed the opinion that these microscopic structures belong to 

 Cyclostomatous fishes, like our modern Lamprey and Hag-fish, and 

 were not referable to either Annelida or Mollusca. This opinion 

 was also shared by the late Prof. Huxley, who examined a series 

 submitted to him by Dr. G. J. Hinde. 



In 1894, Dr. E. H. Traquair described a remarkable fossil from 

 the Old Eed Sandstone of Scotland, being the nearly complete 

 skeleton of a small creature, about an inch in length, having a 

 calcified skeleton, the general aspect of the skull resembling that 

 of a recent Lamprey, with no evidence of jaws or separate ossifica- 

 tions, but with well-calcified ring-vertebrae, and neural and hremal 

 spines. 



A single species, named Pcdeeosponchjlus Gunni, has been found 

 in the Caithness Flagstones near Thurso. 



Another primitive group, the Ostracodermi, appears in the 

 Upper Silurian and Lower Devonian, and exhibits no trace of jaws 

 or of a segmented axial skeleton or arches for the support of paired 

 Hmbs, but median fins are present ; with no hard internal skeleton, 

 and with the notochord persistent. 



The head and trunk are invested with a dermal armour, and 

 in addition to the shield covering the head there is usually one 

 covering the abdomen, and a ventral plate meeting the dorsal on 



l 2 



