Movements of JCL : SD male rat infants were observed daily for 3 minutes from day 1 to 21 after birth in the open field apparatus. Head-slow-waving appeared after head-up and head-waving, followed by pivoting, crawling, creeping, walking and standing. Activity of the rat infant was measured by ambulation in the open field apparatus. The four phases in the development of locomotion (head movement, pivoting, crawling and creeping, and walking) corresponded to four periods in the development of ambulation. Grooming patterns developed in the order of paw-licking, face-washing and fur-licking.
The order of the appearance of movement and grooming patterns in JCL : SD adult male rats on the table were observed. Adult rats displayed movement patterns in the order of pivoting, walking and standing, and showed grooming patterns in the order of paw-licking, face-washing and fur-licking. These orders are essentially the same as in infantile behavioral development in rats. The present findings suggest that the successive occurrence of these movement and grooming patterns in the adult rat repeats the developmental order of both patterns in infant behavior.

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The present experiments investigated the feature-positive effect with pigeons using spatial positional cue. A horizontal stimulus array composed of seven translucent plexiglasses, square response keys (1.5 × 1.5 cm) was mounted on the front panel. The position of a lit key served as a stimulus (Fig. 1).
In Experiment 1, stimulus control of the positional cue was ascertained using successive discrimination training and generalization procedure (Figs. 2 and 3).
In Experiment 2, for half of the pigeons, responses to displays containing the distinctive feature (“D”) were reinforced (feature-positive, FP), and for the remaining pigeons responses to displays without “D” were reinforced (featurenegative, FN). A particular position of a lit key served as the “D”, and the other position of a lit key served as the common feature (“C”). The position of a lit key was denoted as “1”, “2”, ...., “7” from left to right of the front panel. The “D” was either “1”, “4”, or “7”. Each subject was assigned to one of the three “D” s. A discrimination was trained between a single stimulus and a pair of stimului (Fig. 4), until the discrimination criterion had been attained or 30 training sessions had passed.
On the day following discrimination training completed, a generalization test in extinction was performed for all pigeons. Two out of seven keys were lit simultaneously. The combination of stimuli and the order of presentation of the combination were randomized.
Discrimination performance revealed that FP-subjects localized responses on the “D” and learned the discrimination easily, whearas FN-subjects localized responses on the “C” and did not learn the discrimination (Figs. 5 and 6). Thus, feature-positive effect was observed using positional cue.
All FP-subjects showed ordinary convex excitatory generalization gradients arround the position of the “D”, but only one pigeon in FN condition revealed concave inhibitory gradient. The “D” for this pigeon was “4”, and the discrimination ratio of the pigeon was about. 70 on the final session of the discrimination training. Other FN-subjects showed flat gradients.
In Experiment 3, only the stimulus position of “3”, “4”, and “5” were used. This display was compact and was suggested to show a better stimulus control in Experiment 2. A discrimination training and a generalization test were performed as same as Experiment 2 except for the number of stimulus combination. The discrimination performance of FN-subjects were better than FN-subjects in Experiment 2. Generalization gradients were concave for all FN-subjects.
From the results of Experiments 2 and 3, the followings were concluded : (1) The feature-positive effect was observed using only positional cue in pigeons. (2) Proximity of “D” with “C” is an important variable for the acquisition of an inhibitory stimulus control of “D” in FN condition.

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前報告 (3) では隔離飼育ニホンザル成体の攻撃性について検討がなされ, 隔離飼育オスが非常に攻撃的である一方, 対照群である自然集団育ちの個体はオスメスを問わず攻撃性の低いことが示された。そこで, ここでは自然集団育ちの成体オスをいくつかの事態で出会わせることによって, 彼らの同性個体に対する攻撃性がいかなる要因によって規定されているかを探り, それをもとにしてニホンザルの社会性およびその力動性に関する若干の指摘を行ないたい。設定した事態としては,
(1) 非交尾期における成体オス同士の出会わせ,
(2) 交尾期における成体オス同士の出会わせ,
(3) 交尾期における成体オス同士に成体の新奇刺激個体1頭を呈示する3者事態,
の3種類であり, 時期に規定される性的活動性の高低と第3個体の存否およびその性が変数とされる。

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The drinking patterns of water and 3 ethanol solutions (5, 10, 15%, w/v) in the schedule-induced polydipsia session (1 hr) and blood alcohol levels thereafter were examined using 8 male rats of the Wistar strain. Compared withh the other two ethanol solutions, the 5% solution was consumed in a larger quantity (Fig. 2), and it was consumed more continuously (Fig. 1 and 4). This would induce a higher blood alcohol level after the session (Fig.3).

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