7o NATURAL SCIENCE. July. 



depths at which certain species occur. Between 1862 and 1866 Mr. 

 J. Y. Johnson continued Lowe's investigations, though not clearly 

 perceiving the significance of the many deep-sea fishes he discovered. 

 During the decade following i860, Dr. Gunther himself also discussed 

 the bearing of these discoveries, with what is now proved to have 

 been much foresight; and by 1870 the time had arrived for some 

 definite and systematic attempt to solve the various problems that 

 had arisen. The voyage of the " Challenger " was precisely oppor- 

 tune, and the naturalists in charge obtained no less than 610 speci- 

 mens, all carefully localised, and many with an approximate record 

 of the depth at which they were captured. It then became clear that 

 the deep-sea fishes had a very wide distribution, and some were 

 definitely proved to live at no less great a depth than 2,750 fathoms. 

 Ample material was also furnished for an examination of the so-called 

 " eye-spots " on these remarkable animals (PI. xvi., Fig. 4) ; and the 

 researches of Moseley and von Lendenfeld (forming a supplement to 

 Dr. Giinther's report) gave the first adequate idea of the structure of 

 these organs. It is now certain that they produce light, and at least 

 the more specialised of them appear to be directly under the control of 

 the will of the fish. The most interesting general result of the 

 " Challenger " work, however, was the proof that all the deep-sea 

 fishes are modifications of forms still inhabiting the shallower waters. 

 Bathyptevois, for instance (PI. xvi., Fig. 3), is a new Scopeloid genus which 

 has retained much of the outward appearance of surface fishes, and 

 might be thought equally well organised for life in some quiet dark 

 water near to the surface. The chief modification is in the pectoral 

 rays, which are much elongated, some of the upper ones being separated 

 from the remainder of the fin. They are evidently organs of touch, 

 enabling the fish to examine objects hidden in the ooze, which its 

 imperfect eyes could not detect. The Palaeontologist might have 

 expected to find among the deep-sea fishes a few refugees from an 

 older fauna ; but none of them represent types earlier than those of 

 the Cretaceous period. The few very antique fishes that remain have 

 taken refuge in the fresh waters, or become adapted to the present 

 conditions of the shore and open ocean. 



The only report on Reptiles is a short memoir on the develop- 

 ment of the Green Turtle, contributed by the late Dr. W. K. Parker 

 to the first volume in 1880. This is based on a collection of embryos 

 brought from Ascension by the Expedition, and on other specimens 

 subsequently collected in the same place by Dr. Maclean, R.N. It is 

 illustrated by no less than thirteen plates, and gives the first detailed 

 account of the development of the skull in the Turtles. Some of the 

 more striking embryos themselves are also briefly described, and 

 Dr. Parker particularly emphasises the fact that they exhibit many 

 more body-segments, especially in the neck and tail, than might be 

 expected from the number of vertebrae in the adult. 



A. Smith Woodward. 



