32 



EINAR LEA. 



[REP. OF THE "MICHAEL SARS" NORTH 



by Bellotti, which is certainly less advanced in its devel- 

 opment, The alimentary canal has the two characteristic 

 dilatations which are also present in L. stylunis and 

 Hyoprorus messinensis. The snout projects, beyond the 

 tip of the under-jaw and is pointed. 



The total length of our specimen is about 92 mm 

 and the greatest height almost 5 mm. 



Distance from point of snout to anus 24 mm and to 

 the beginning of the dorsal fin about 12 mm. 



Fig. 32. L. Saurenchelydis cancrivorae. 10 /i. 



Length of head 6-2 mm, distance from point of snout to 

 anterior margin of eye 2-8 mm, and diameter of eye 0-7 mm. 



The number of myomeres is about 249, 48 of which 

 are preanal and 201 postanal. The myomeres are of the 

 usual shape with angles dorsally and ventrally. 



Teeth are present, but they are small. In each half 

 of the upper jaw there are about 1 + 1 + 16 and in 

 each half of the lower jaw 1 + 16. 



The anterior nostril, which is placed rather near the 

 point of the snout, shows indications of a tubular shape. 

 The posterior nostril is a somewhat oval pore placed in 

 front of the eye. 



. Mucous pores are present on the head as shown in fig. 32. 



The rays of the fins are distinctly developed. The 

 dorsal fin commences not far from the occiput, and the 

 anal fin close behind the anus. 



As far as I can see the caudal fin contains 6 rays, 

 3 on each hypural. 



I have not been able to discover the slightest trace 

 of pectoral fins. 



On the head there is pigment placed on the points 

 of the snout and the lower jaw, and a couple of rather 

 large spots across the brain portion. A series of dots 

 extends along the alimentary canal, and there is a series 

 of small dispersed points on the transparent portion be- 

 tween the anal fin and the muscular system of the body, 

 and dots at the bases of the foremost rays in the anal fin. 



19. Leptocephalus urosema n. sp. 



Two specimens of this species were taken at Stats. 53 

 and 56 in 100 metres. One specimen was somewhat 

 damaged, but is was possible to count the segments in 



the other; there were 64 preanal and about 126 postanal 

 segments, altogether about 190. 



In general appearance this species resembles Hyo- 

 prorus messinensis Kdlliker and L. hyoproroides Stromman. 



Fig. 5, pi. V shows these larvae to be high in relation 

 to length, and they attain their greatest height nearer the 

 head than the tail. At the lateral line the myomeres form 

 a very obtuse angle which is not very much smaller 

 than 180°. 



The pigmentation in this species is very characteristic. 

 A big spot on a level with the lateral line, apparently 

 inside the skin, may be seen in fig. 5, pi. V. The distance 

 from this spot to the tip of the tail in the undamaged 

 larva is 5 mm. 



We find two pigmented swellings on the intestinal 

 canal, which feature it has in common with Hyoprorus 

 messinensis, figured by Kaup (22), and with the two 

 species L. Saurenchelydis cancrivorae and L. stylurus 

 described in this work. 



As for the head it has some pigment along the 

 posterior margin of the eye, on the snout and the lower 

 jaw, and a crescent-shaped spot on the gill portion, as 

 shown in fig. 33. 



The intestinal canal shows, besides the two above- 

 mentioned swellings, a dilatation in front of the embryonic 

 pectoral fin (seen in fig. 33). The canal is very thin from 

 the foremost swelling to the second one, but between the 

 second and third swellings, it gradually becomes thicker, 



Fig. 33. Head of L. urosema. 15 /i. 



then tapers off towards the anal aperture. No trace of 

 true rays was found in any of the fins, and there is not 

 even an indication of interspinous elements or hypurals 

 in the vertical or caudal fins. The point of the notochord 

 is straight. 



The head shown in fig. 33, has the usual form; the 

 snout is not very long, but slender and pointed. 



The teeth are small, but it is evident that these two 

 larvae are only slightly developed. The foremost tooth 



