150 A. Smith Woodward — Fish Fauna of Purheck Beds. 



of Mr. Andrews' fossil entitle it to specific distinction, and it may 

 appropriately bear the name of M. Atidrewsi in compliment to its 

 discoverer. 



Horizon and Locality. — Middle Purbeck : Teffont. 



Fry of PleurophoUs. — Plate YII. Pig. 4, 



The considerable thickness of the scales in PleuropJioUs has hitherto 

 prevented any glimpse being obtained of the internal skeleton in that 

 genus. It is therefore of interest to find in Mr. Andrews' collection 

 some immature individuals in which the squamation is still un- 

 developed. One of these is shown of the natural size in PI, VII. 

 Pig. 4, and exhibits the greater part of the skeleton. 



The notochord must have been persistent, but the arches are robust. 

 In the abdominal region the neural arches and their spines are 

 separate ; but in the caudal region both the neural and haemal spines 

 are shown to be directly fused with their supporting arches. There 

 are well- developed, though slender, ribs, not reaching the ventral 

 region. The tail ends in a slender upturned production of the noto- 

 chord, with expanded haemal spines below'. The small pelvic fins 

 are situated midway between the pectorals and the anal ; the dorsal 

 and anal fins are large, and their rays are proved to be exactly equal 

 in number to the supports. The only trace of the squamation is the 

 middle portion of the deep fiank- series, which exhibits a certain 

 amount of superficial ganoine. 



Horizon and Locality. — Lower Purbeck : Teffont. 



Leptolepis Brodiei, Egerton. Plate VII. Pigs. 5, 6. 



[Brodie's Poss. Insects, 1845, p. 15, pi. i. figs. 1-3.] 



The fine new specimens of this diminutive fish collected by Mr. 

 Andrews add a little to our knowledge of the species ; and two 

 examples of the trunk are shown of the natural size in PI. VII. 

 Pigs 5, 6. 



The caudal vertebrae are now proved to be about twenty, and the 

 abdominal vertebrae also not less than twenty in number. Inter- 

 muscular bones are conspicuous in the abdominal region of the original 

 of Pig. 5, and there also appear to be traces of the short free neural 

 spines. The small pelvic fins, each with about eight rays, arise 

 opposite to the origin of the dorsal. The latter is large, comprising 

 ten rays, of which the first three are much closer together than the 

 others. The anal fin arises considerably behind the middle point 

 between the pelvics and the caudal, and is veiy small and low, com- 

 prising seven rays. The caudal fin, hitherto unknown, is very robust, 

 consisting of stouter rays than those in any of the other fins. A long 

 mass of coprolitic matter (c) is observable in the original of Pig. 6, 

 between the pelvic and anal fins, indicating that the anal opening 

 must have been situated immediately in front of the latter fin. 



Horizon and Locality. — Lower Purbeck : Lime Kiln Quarry, Teffont. 



2. Some undesckibed Jaws of Pishes feom the Purbeckian- of 



SwajStage, Doesetshihe. 

 There are still several undescribed fishes represented by fragmentary 

 remains from the Purbeck Beds of Swanage. Among these fossils are 



