The present paper, the eighth of the series of the pelagic fish eggs from Japanese waters, contains the figures and descriptions of 21 species belonging to the suborder Cottina.
The fishes of this suborder are oviparous or ovoviviparous, and oviparous members beget pelagic or demersal eggs. Japanese species, which spawn the pelagic eggs, are Sebastolobus macrochir (CÜNTHER), Pterois lunulata TEMMINCK et SCHLEGEL, Inimicus japonicus (CuvIER et VALENCIENNES), Hypodytes rubripinnis (TEMMINCK et SCHLEGEL), Scorpaenidae-type Nos. 1-9, Platycephalus indicus (LINNÉ), Cheridonichthys kumu (LESSON et GARNOT), Pachytrigla alata (HOUTTUYN), Lepidotrigla, japonica (BLEEKER), L. microptera GÜNTHER and Triglidae Nos. 1-3.
Among the pelagic eggs of Cottina, as far as known, those of the family Scorpaenidae are agglutinated in one mass, and isolated in Synanceiidae, Congiopodidae, Platycephalidae and Triglidae. Both isolated and agglutinated eggs are globular in shape, 0.69-1.46 mm in diameter, the egg membrane is smooth, without any conspicuous structure, the yolk not segmented, the perivitelline space narrow. Most species possess a single oil globule in the egg, in some lacking it. In the course of the egg development melanophores and xanthophores appear on the em bryonal body, yolk, marginal fin and oil globule in many species, in some species lacking one or both pigment-cells of some part, rarely no pigment-cell at all.
The oil globule of the newly hatched larva, if present, is situated in the posterior part of the yolk. The number of myotomes of the hatched larva is 26-35. Excepting P. indicus, the pectoral fins become conspicuously large in the larval development, usually covered with pigment-cells.

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The present paper, the tenth of the series of the pelagic fish eggs from Japanese waters, contains the figures and descriptions of 9 species belonging to the orders Gadida and Lophiida.
Gadida. The egg and larval development of Theragra chalcogramma (PALLAS) and Gadida Nos. 1-3 are known from Japanese waters. These eggs are globular in shape, 0.63-1.70 mm in diameter. The egg membrane is smooth, without any conspicuous structure, the yolk not segmented, the perivitelline space narrow. The oil globule is absent in T. chalcogramma (5-6 very small ones are present in early developmental stage, but they disappear during the develoment), or single one is present in Gadida Nos. 1-3. Only the melanophores appear in the egg and they are restricted on the embryonal body in T. chalcogramma, while melanophores and xanthophores appear on the embryonal body and oil globule in Gadida Nos. 1-3. The number of myotomes of the hatched larva is 35-50. The anus is situated the just behind the yolk, not reaching the fringe of the marginal fin, and it shifts forward during the larval development. The body surface is covered with granules.
Lophiida. The egg and larval development of Lophius litulon (JORDAN), Lohius sp., Pterophryne histrio (LINNÉ), Antennarius sp.and Agglutinated eeg No.2 (probably belonging to this order) are known from Japanese waters. Excepting Agglutinated egg No.2, these species spawn gelatinous egg veil. The egg veil of Lophiidae is long, nearly 5 m in length, but that of Antennariidae is rather short, less than 1 m in length and surface of the veil is covered with fine hexagonal mesh structure. The eggs of both family are imbedded in gelatinous substance in 1-3 layers, and 1-5 eggs are confined in a hexagonal or pentagonal compartment. The egg of Lophiidae is nearly globular in shape, 1.30-1.70 mm in diameter, containing a single oil globule measuring 0.33-0.35 mm in diameter. The egg of Antennariidae is ellipsoidal in shape, 0.62-0.98×0.52-0.70 mm in diameter, lacking the oil globule. The egg membrane of both family is thin (especially in early developmental stages), with out any conspicuous structure. The yolk is not segmented, but in Antennariidae hexagonal networks appear on the yolk surface as well as on the body and marginal fin at the late embryonic stage. The perivitelline space is narrow. Only the melanophores appear in the egg and larval development. The number of myotomes of the hatched larva is 18-32. In the hatched larva of Lophiidae dorsal and ventral fin rays appear before the comsumption of the yolk.
The eggs of Agglutinated egg No.2 are sticking to each other to form egg mass, without gelatinous substance. The number of the eggs of one mass seemed to be 5-10. The egg is nearly globular in shape, 0.70-0.74 mm in diameter, lacking oil globule. The egg and larval development are much the same as those of Antennariidae.

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