Washburn, Cor7iparative Psychology. 517 



as to whether the crab or the actinian started the fashion of the latter's taking up 

 its abode on the former's back. 



56, 57, 58, 61. The first of the reports by Pieron to the Society of Biology 

 regarding his studies on ants states that he has confirmed with eighteen hitherto 

 untested combinations of species, Bethe's experiment in which an ant was received 

 into a foreign nest when dipped in the juices of ants from that nest. In the second 

 paper (57), he notes various circumstances which modify the reaction to strangers. 

 Certain species are incHned to be tolerant, such as Aphaenogaster barbara nigra 

 and Formica cinerea with regard to other nests of the same species, and Myrmecina 

 latreillei with regard to other species. Sometimes an ant of the same nest is attacked 

 "erroneously." Attacks are more frequent near the nest than at a distance from 

 it. A solitary ant tends to run away rather than to attack, save in the case of a 

 very small one meeting an ant of a larger species, when the former clings to the 

 legs of the latter. Males do not distinguish strangers from nestmates, and a 

 female after the nuptial flight is received in a foreign nest. There are also individ- 

 ual differences in reaction. Most of these modifying circumstances have an 

 adaptive significance (58), for instance the tolerance of Formica cinerea is doubt- 

 less connected with the fact that its nests are ordinarily built close together, 

 and that of Myrmecina may be due to its hard chitinous armor. As regards the 

 problem of nest finding, PiERON would distinguish three types of ants: visual 

 (Formica fusca, e.g., which cannot find the nest when blinded), olfactory (Lasius 

 fuliginosus, e.g.), and muscular (Aphaenogaster barbara, which if carried out of 

 its path will continue, when set down, until it reaches a point where the opening of 

 its nest would have been found if the ant had not been moved). 



59, 60, 63. We have already noted under (8) the contents of paper 59 

 and Pieron's distinction between "anticipation," or reaction which is made 

 ahead of time because it has become associated with an an external stimulus occur- 

 ring before the original stimulus to the reaction, and rhythmic reaction, where the 

 response is made to an internal state of the organism, which has come to be period- 

 ically produced. In papers 60 and 63 this distinction is amplified and the 

 general significance of physiological rhythms considered. 



62, 64, 65, 66, 67. The chief point of importance brought out in the discussion 

 of autotomy or self-amputation is Pieron's differentiation of a form of the phenome- 

 non which he calls "psychic autotomy," unlike reflex autotomy in the facts that it 

 is made in response to slight stimulation, such as merely holding the member fast, 

 and that it does not occur if the commissures connecting the cerebral ganglia with 

 the ventral ganglia are cut. Drzewina (30, 31) sees no reason to distinguish this 

 phenomenon from ordinary reflex autotomy, and has found it occurrmg after 

 section of the commissures. 



68. Retterer states that actinians in northern seas where the effect of the tides 

 is less marked do not show a tidal rhythm in the laboratory. 



69. This paper is a study of the manner in which certain seaside Diptera are 

 adapted to their surroundings. The bodies of most of them are impervious to 

 water; those which are by their manner of life exposed to the wind have a marked 

 tendency to orient to it, or to hide behind shells when it is very strong; other forms 

 resist it by taking very short flights or by bracing themselves with their legs. 



70. The following three points are brought out in this study of Actinia equina. 

 (a) 1 he actinian tends to resume the position it had in nature when placed in 



