At Mentone I have never found more than this one specimen, and the ants among which it was domiciliated were of a species new to me (_Camponotus_ (_Formica_) _lateralis_, Oliv.). This colony of ants was composed of many winged males and females, as well as workers, the last-named measuring from two and a half to three lines in length, and black in colour. In other colonies I have found the workers black, with red head and thorax. Another ant, not enumerated in my list in _Ants and Spiders_, is _Camponotus_ (_Formica_) _sylvatica_, which I detected in March last under stones on Cap Martin, near Mentone. When disturbed, this ant runs along with its abdomen raised vertically in the air, much as the devil's coachhorse (_Staphylinus_) does. The same curious habit of erecting the abdomen is found in another ant, not uncommon in decaying wood in the South, _Crematogaster scutellaris_; and probably all three insects adopt this threatening attitude, which is that of the scorpion preparing to strike and sting, in order to intimidate their enemies, though _Crematogaster_ is the only one which really possesses a sting. _Camponotus sylvatica_ has the same long legs and slender body as _Formica cursor_, and is of about the same size; the workers, which are of a dark brown colour, measuring about 3-1/2 lines in length. Perhaps it may be well, in concluding these remarks on Harvesting Ants, to call attention to the principal questions which still await solution. The first is one which any observer who travels in Central Europe during the summer may help to solve. 1. Do _any_ ants collect and store seed in Switzerland, Germany, North France, England, or indeed in any of the colder parts of the world? 2. What are the habits of _Atta structor_ and _A. barbara_ when living, as they are known to do, in Switzerland, Germany, and Northern France? 3. How do the ants contrive to preserve the seeds in their granaries free from germination and decay? 4. How are the seed-stores of tropical ants disposed below ground, and of what do they consist? 5. Do harvesting ants exist in the southern states of North America, in Australia, New Zealand, or at the Cape? SUPPLEMENT TO TRAP-DOOR SPIDERS.