_Icterus portoricensis_, p. 280. Owl, p. 351. Partridge, p. 278. _Phasianus_ sp., p. 277. Sparrow, p. 282. _Tiaris bicolor omissa_, p. 282. _Tockus birostris_, p. 279. _Troglodytes aedon_, p. 281. _Troglodytes audax_, p. 281. Mammals: _Bassariscus astutus_, p. 288. _Callithrix jacchus_, p. 285. _Erinaceus_ sp., p. 283. _Felis catus_, p. 289. _Felis paradalis mearnsi_, p. 290. _Herpestes javanicus auropunctatus_, p. 289 _Herpestes_ sp., p. 289. _Homo sapiens_, p. 287. _Loris tardigradus_, p. 284. _Molossus_ sp., p. 283. _Monodelphis_ sp., p. 283. _Nasua nasua_, p. 288. _Nasua_ sp., p. 289. _Rattus_ sp., p. 287. XV. COCKROACHES AS COMMENSALS These particular associations may well have been accidental and due to a predilection for the same type of nesting site. But this fact in no way detracts from the interest of such records. Chance must play a very considerable part in first bringing symbiotic or commensal partners together. Once such a partnership between species has been firmly established, it is on the whole, fairly obvious, ... On the other hand, in the early stages before the relationship has become fixed as a specific habit, individual cases are generally dismissed as coincidences. It is, however, unwise to disregard such isolated observations or dismiss them lightly. ROTHSCHILD AND CLAY (1957) The following social insects have been found harboring cockroaches in a state of commensalism in which the cockroaches presumably benefit by acquiring food from their hosts. Benefits accruing to the hosts are not apparent. Unfortunately, biological details are not always sufficient to substantiate the suspected association. However, it seems significant that the cockroach commensals of the insects listed below have been found only in association with their hosts and, so far as we know, have never been found apart from them. Chopard (1938) has pointed out that the myrmecophilous cockroaches are all small, being only a very few millimeters long; they are apterous or subapterous; their eyes are reduced; and they are all of American origin. HOSTS OF COMMENSAL COCKROACHES Order ISOPTERA Family RHINOTERMITIDAE =Coptotermes ceylonicus= Holmgren _Commensal._--_Sphecophila ravana_, Ceylon (Fernando, 1957): Six females, 50 males, and nymphs of both sexes were found among decaying timber in the ground in association with a colony of this termite. The antennae of most specimens were mutilated unsymmetrically. Family TERMITIDAE =Macrotermes barneyi= Light _Commensal._--_Nocticola sinensis_, Kowloon (Silvestri, 1947): Among specimens of termites collected from a nest. =Macrotermes bellicosus= (Smeathman) or =Macrotermes natalensis= (Haviland) _Synonymy._--_Termes bellicosus_ [Snyder, 1949].