A single gobiid specimen identified with Oxyurichthys ophthalmonema (Bleeker) was obtained from the mouth of the River Shimoyama, Hayama, Kanagawa Prefecture, September 19, 1970.To my knowledge, this species has not yet been recorded from Japan.As this goby is found in southern waters, this individual probably strayed from the south. Tomiyama (1936: 79) reported O.tentacularis (not of Cuvier and Valenciennes) based on two specimens from Taiwan and called them “matsugehaze” in Japanese. Besides the three specimens mentioned above, the syntypes of Gobius tentacularis Cuvier and Valenciennes, and the holotype of G.ophthalmonema Bleeker, were examined morpholog-ically together with many other specimens belonging to O.ophthalmonema or O.tentacularis listed on page 105. Though Tomiyama (1936: 79) considered that G.ophthalmonema Bleeker is synonymous with his O.tentacularis (not of Cuvier and Valenciennes), the result of the present study revealed that O.ophthalmonema (Bleeker) and O.tentacularis (Cuvier and Valenciennes) are distinguished from each other significantly because of the following reasons. (1) In O.ophthalmonema the upper and lower rims of the upper lip are almost parallel with each other, but in 0.tentacularis the upper lip is constricted at the centre (Fig.2 and Table 2). (2) The spine of the first dorsal fin of 0.ophthalmonema is much longer than that of O.tentacularis in proportion to the standard length (Table 3). (3) The head of O.ophthalmonema is also somewhat longer than that of 0.tentacularis in proportion to the standard length (Table 4). (4) The length of the ascending process of the premaxillary of O.ophthalmonema is shorter, and its articular process is wider and clearly discernible from the ascending process, while the articular process of O.tentacularis has no apex and thus is not clearly distinguishable from the ascending process except for one among five specimens examined (Fig.4 and Table 5). Reexamination ot two specimens reported by Tomiyama (1936) revealed that they belong to O.ophthalmonema.
Observations on the spawning behavior of the fluvial dwarf form of masu salmon, Oncorhynchus masou (Brevoort), were made in the Ishido-dani, a tributary of Hitotsuse River in Miyazaki Pref., in the autumn of 1957 and 1969.During the spawning season from the last part of October to the first part of November, the water temperature was 13.5-15.5°C and the spawning act of a female and several males was observed usually in the pool-end. In the male group the hierarchy of peck-right type is recognized according to their body sizes and the largest one mates with the female.The paired male immediately drives subordinate males away if they attempt to approach the female.The female defends her site from invaders such as males which are smaller than herself or another female which tries to dig the site of the paired female. The feeling and/or crouch (Fig.6 C and D) of the female is thought to be the signal posture that causes courting of males, and when the paired male is in the similar posture, homosexual courtship of another smaller male is occasionally observed.As the female repeats digging movement at the rate of twice a minute, a shallow depression is made in which the oviposition occurs.At the oviposition, 30-100 eggs are shed into the crevices of gravel remained in the center of the depression.In the postspawning stage only the female remains on her redd and she covers the eggs with sand and smaller gravel of the upstream part from the depression. Several hours after the first oviposition, the males appear again near the female which is making another depression at about 20 cm upstream place from the previous one, and they repeat the same acts as they did in the first prespawning stage.The next oviposition is usually observed 25-30 hours after the first one.Three or 4 days are necessary for 2 or 3 times of oviposition.