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Part III. — Seventh Annual Report 



The pectoral fins are large, and a marginal (embryonic) tin occurs along 

 the ventral edge of the abdomen. The latter is translucent, and presents 

 an opacity in front (liver), beneath which lies a small yellowish oil-globule, 

 so that the ovum likewise possesses this feature. The vent is prominent and 

 open. Black pigment-corpuscles are grouped along the roof of the abdo- 

 men in the usual position, while a single one lay over the liver. A row 

 of these also runs along the base of the dorsal marginal fin from the head 

 to the tail, and a similar series exists along the ventral border from the 

 vent to the tail. Over the faintly yellowish mid-brain are five isolated 

 black specks, followed by an interval, after which the dorsal row com- 

 mences. When viewed laterally, it is difficult to keep the head in position, 

 from the great size of the eyes, the inferior border of which abuts close on 

 the maxillary margin. The otocysts are large, and lie close behind the eyes. 



Another and somewhat younger example (Plate HI. fig. 5), subse- 

 quently procured, shows the peculiar character of the cerebral pigment some- 

 what better (fig. 7), though the yolk was not yet completely absorbed. 



It is difficult at present to give the relationships of this form, but the 

 great size of the eye, the shortness of the snout in front of it, the 

 upward slope of the mandible, and the pigment distinguish it from any 

 form hitherto seen. 



During this month the pelagic ova of the long rough dab should be 

 abundant, as the adults are now ripe. 



Moreover, at the end of the month a female bib was found with 

 perfectly ripe ova, so that in all probability these will occasionally be 

 procured in the bay about this time. The breeding season of this 

 species, therefore, would seem to be much earlier than that of the poor 

 cod, which does not spawn at St Andrews, as a rule, till June or July. 

 The egg-capsule is finely punctured as in the plaice, and the micropyle 

 resembles that of the haddock. 



Makch. 



Pelagic plant life in March consisted of many diatoms, spores of Alga3, 

 and often of Rhizosolenice. Every cast of the net, especially at the bottom 

 and surface, teemed with these structures towards the end of the month. 



The only Infusorian recognised was Ceratium tripos, though many of 

 of the more minute forms were also present. 



The Coelenterates occurred chiefly in the mid-water net, and included 

 Circe and Pleurobrachia, the former appearing often in very great numbers, 

 and indeed forming a feature in the collections of the period, both in the 

 mid- water and bottom nets. Both large and small examples were present, 

 but the majority were full grown. Pleurobrachia was almost as abun- 

 dant, but the majority of the examples were small, though occasionally 

 some reached § inch. Minute forms abounded in the trawl-like bottom- 

 net towards the end of the month. Ctelenterate life was much more 

 abundant; thus swarms of Ephyra3 of Aurelia and probably of Cyanea 

 also were present ; indeed, in former years they appeared to have been 

 pumped with the water into the laboratory, since every vessel contained 

 them in March 1887. Minute specimens of Thaumantias lucifera, 

 Oceania (Tiara) octona, and Lizzia octopunctata, and other forms 

 occurred in the same net, which also captured many young examples of 

 Lexuewria scarcely visible to the naked eye. A single example of Bou- 

 gainvillia britannica (Margelis ramosa, A. Agassiz) was also obtained by 

 the mid- water net. Thus a wealth of medusoid life is found close to the 

 bottom at this season, and such is the most likely area in which to find 

 Epliyrai and Medusa-buds. 



