This study was conducted on a free-ranging group of Japanese macaques (Macaca fuscata) at Katsuyama, Okayama Prefecture for 52 days during the period from June 1977 through June 1978. A total of 119 animals over the age of three years were observed and a total of 2, 467 bouts of groomings were collected.
Of all the grooming bouts observed, 1, 561 (63. 3%) were between relatives. Of all the grooming between relatives, slightly less than 80% of groomings were performed between mothers and daughters. In both mating and non-mating seasons, groomings occurred predominantly between females. But in the mating season, the occurrences of cross-genealogical groomings between females decreased from 35. 8% to 12. 8% of all the grooming (Table 1).
In cross-genealogical grooming between females, animals tended to groom dominant ones (73. 1%) more often than they did subordinate ones (26. 9%) (Fig. 1). Analysis of grooming relationships between non-genealogical females according to age differences indicated that occurrences of grooming declined with increasing age differences (Fig. 3).
With respect to the characteristic of each genealogy in grooming relationships, animals in lower-ranking genealogies had grooming relationships predominantly with animals in their own genealogy. Proportion of groomings done by animals in lower-ranking genealogies declined with decreasing dominance ranking of genealogy. Grooming relationships between central males and females were maily determined by the leader-follower relationships rather than by the dominance relationships (Tables 2 and 3).
These results illustrate that groomings performed between relatives differ from those performed between non-genealogical animals with respect to primary function of grooming, and that cross-genealogical groomings play an important role in integrating animals separated by kinship into a group.

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The purpose of the present study was to investigate the effects of the extroceptive stimulus control upon the time discrimination behavior in rats, under the mult DRL DRL schedule having two different training conditions. A half of Ss were examined in a modified Skinner box, and they could avail themselfes of water lickings in it (the WA group, N=10), but another half of Ss were trained in a standard Skinner box, then they made not use of water lickings (the NWA group, N=9). In the former training condition, the development of the water licking behavior regarded as a kind of collateral behavior, was supposed to strengthen the effects of the proprioceptive stimulus control upon the time discrimination behavior in the DRL schedule, conquerring the effects of the extroceptive stimulus control.
After some routine preliminary training sessions, 19 rats of the Wistar strain were exposed to a mult DRL 10-sec DRL 20-sec schedule, in which these DRL components were shifted in a regular turn, and the light or tone presentation was used as the cue stimulus coresponding to each DRL component. These daily training sessions for 41 min were carried out for 36 consecutive days. Both groups were examined with the same procedure except for the availability of water lickings.
In general, most of the Ss in both groups could discriminate their bar pressing patterns between the DRL 10 and the DRL 20. Some clear differences in their behavior patterns were found depending upon the availability of water lickings. In the WA group, the development of collateral behavior brought about much lowered overall rates of bar pressings (Fig. 1, Table 1), therefore much better efficiency of bar pressings for getting reinforcements was observed in both DRL components. However, in spite of these advantages, the Ss of the WA group showed relatively poor discrimination between the DRL 10 and the DRL 20. They also showed poorer timing behavior to estimate the reinforcement requirementtime, especially in the DRL 10 (Fig. 3). On the other hand, the Ss of the NWA group discriminated between the DRL 10 and the DRL 20 more precisely, and performed their bar pressings more suitably, in both components. The Ss of the WA group were affected not only by the proprioceptive stimulus control, but by the extroceptive one. The poorer time discrimination in them would probably due to the indistinct contingency of reinforcements caused from the prolonged water lickings in every inter bar-pressing interval. The mult DRL 10 DRL 20 used in the present experiment had a limited hold (LH) condition in neither component, so that the unnecssarily longer spaced bar pressings might be facilitated with water licking behavior, especially in the DRL 20 of the WA group.
These results were substantially in accordance with our working hypothesis on the relative predominance of the proprioceptive stimulus control over the extroceptive one.

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