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number of interesting notes, reported a Sabine's Gull Aying over the harbour on 17th. On 2nd amongst a number of Yellow Wagtails on the denes, was an undoubted Blue-headed Wagtail, distinguishable from the yellow ones by its generally lighter colour, blue-grey head and white eye-stripe : another of the same species [or race] was seen on 17th. An adult female Marsh Harrier was beating over Benacre broad on 30th.

JUNE.—At least four pairs of Crested Grebes were to be seen about Oulton Broad, and probably nested there. A shot ' pricked ' male Goldeneye remained on the broad throughout the summer. Several pairs of Bearded Tits nested along the Waveney between Oulton Broad and St. Olaves.

JULY.—An adult Little Gull was at the Ness Point on 27th.

AUGUST.—Little of outstanding interest occurred during the earlv autumn migration, owing to continued westerlv winds.

On 22nd a Elack-headed Gull was seen Aying up the harbour with a cockle (Cardium edule, Linn.) fast holding its foot. One or two Little Gulls occurred during the month.

SEPTEMBER.—A Purple Sandpiper was seen on 9th and a Snow Bunting on 12th, both are early records. No ' rushes' of migrants occurred and, excepting an odd Pied Flycatcher, one or two Redstarts and two northern Wheatears between 5th and 12th, few interesting species were to be seen.

ON ANTS' METHODS OF COMMUNICATION.

BY B . D . WRAGGE MORLEY.

ALI. Entomologists agree that Ants communicate, when they are able, by touching each other's antennae. Some people say that this method of intercourse is based upon smell, others that the contacts are simply gestures ; but I am inclined to consider it a combination of both. Entomologists are not, however, agreed as to how Ants communicate at an appreciable distance ; some say it is accomplished by smell, others by stridulation or further methods. There are several possible ways in which Ants may hold intercourse, all covered by (a) Tapping on the ground ; (b) Making and hearing sound; (c) Smell; (d) Wireless; (e) Telepathy; (/) Sight ; (g) A sixth, or in Ants nineth, sense.

Before going further into the question, it is necessary to obtain some idea about the possibilities of these divergent methods : how far, for instance, would vibrations of (a) ground-tapping carry and

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how would they be received ? Such would depend largely upon the composition of the soil supporting the A n t ; and its radiation extends from a few inches to a foot which is, I think, the extreme limit, unless Ants possess some super-organ for the reception of such vibrations. They certainly have such an organ as might conceivably be capable of receiving vibrations ; and it is situated in the four anterior tibise, consisting of a swelling of the trachea in that part of the leg. Even if this organ be capable of receiving vibrations, it is unlikely to do so at a greater distance than two feet.

Concerning (b) the raaking and hearing of sound, which is among the chief methods of communication, an Ant must posses s some organ for emitting it by percussion, stridulation or a wind method. Of these percussion instruments are the weakest carriers, and unknown among Insects. Stridulation would carry better, and Acanthomyops nigra, L., is furnished with organs which might be emploved for this purpose, rendered the more probable by analogy with similar powers in Crickets, Grasshoppers and other Orthoptera. We humans communicate by means of wind, by adaptability of our labial organs ; but such method is hardly feasible in Ants for many reasons : Ants have no lungs, also the labial organs are so placed as to preclude all possibility of such intercourse. Hence wind is eliminated, and stridulation becomes the sole probable method.

If sound be thus emitted, how is it heard : are there chrodontial organs ? Their presence has been both asserted and negatived, but some such receptive organs certainly exist. Structural modifications in the antennae, such as were discovered by Sir John Lubbock, might be used for this purpose possibly ; the'r similarity to stethoscopes is remarkable ; and other organs might be similarly employed, such as the Johnstonian and champagnecork ones whose purpose is unknown : the shape of the latter gives rise to the name. Summing up the method of making and hearing sound, we find that, if Ants can both stridulate and hear, it is quite possible within certain limits of distance : naturally the higher the sound the further it will carry. But surely Ants should be capable of hearing higher notes than can humans ; yet they respond to no sound that is much higher than we can hear, and those lower than our ränge are just ordinary vibrations.

Dr. Julian Huxley put forward (c) smell as the method by which Ants communicate at a distance, and referred me to Prof. von Frisch of Munich University. Accordingly I got into touch with him, and here translate his German reply : " In recent years various details have been discovered about the means of communication among Ants. Some kinds, with well-developed senses of smell, communicate with each other in the following manner : These animals, having found a source of food, leave

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behind a trail of scent for thev have, like Bees, in their abdomen scent-ducts. Between the food and their nest, they gently touch the ground with their abdomen-tip, thus leaving a trail of smell.

Then, bv means of beating their feelers and by agitated running to and fro, they alarm other members of the colony who follow the scent-trail back and are thus led to the food. 1 know nothing of the singificance of flowers-scent for communication among flower-seeking Ants." I am certainly prepared to believe some Ants communicate thus, though the method is not applicable to long-distance intercourse, wherein an Ant is unable to touch or see its fellows who are not within, say two feet. For this purpose some sort of sign-language must exist : one smell means a certain thing, another means something quite different. T o do so, the production of a variety of smells is requisite no less than their recognition. This is more feasible in Ants than humans, for the former distinguish between smells as we do between shapes : they would easily recognise a Square smell from a round one.

In this case of scent, two probably insuperable difficulties arise : the origin of the multi-smells and of the aircurrent that would waft them.

The (d) wireless method of communication does not appear very likely, since no such waves have been picked up and no power, such as is necessary to transit sensations, has yet been detected in Ants.

The next method is debatable, though not yet proved to obtain between anv animals at present. Two schools of thought exist concerning (e) telepathy, one maintaining the impossibility for animals which cannot reason to communicate by this means, the other that animals, though unreasonable, are enabled thus to communicate : the latter is the older theory and quite possible in the case of Ants. But the former is the more generally accepted, and has to be satisfied. The curious phenomenon, known to all Lepidopterists as " assembling," has excited interest from the earliest times and never yet met with an adequate explanation : a Moth, most typically of the Bombycid group, calls to her mates by quickly vibrating her very hairy antennae, thus causing the necessary waves in ether for telepathic communication, to which males respond by Sรถcking to her for distances of a mile or further. Similar vibrations, though no similar pilosity, are observable in the antennae of Ants. Sight, as a ( / ) mode of intercourse among the latter, is nullified by the known fact that the majority possess it in no more than a modified form, and that many are quite blind.

It seems, then, that we are driven for an adequate explanation to the Ants' Ninth Sense, which I hope to elaborate in a subsequent paper in these Transactions.