The _abdomen_ is short-oval, and strongly convex above; it is of a dull clay-coloured brown tinged with chocolate, and along the centre of its upper side is a series of six strong angular bars or chevrons of a dark chocolate-brown colour, and pretty distinctly defined, though, when examined closely, broken in parts. The intervening spaces between the angular bars and the sides have a few irregular markings of a similar colour; and they are connected by a longitudinal central line of the same hue running through their apices. The abdomen is very sparingly clothed with hairs and fine bristles; the superior pair of spinners are strong; those of the inferior pair very small and short. Examples of this fine and very distinct spider were found at Bordeaux in simple unbranched tubes, covered with a wafer-lid, running down very deep into the earth, in some cases as much as fifteen inches into an exceedingly hard soil, making it a work of great labour and care to get them out without injury. This species can scarcely be confused with any other yet known; its short robust form, short legs, more elevated caput, general dark colour, distinct angular bars on the abdomen, and almost contiguous lateral eyes, as well as the form of the nest, will readily distinguish it. It is with great pleasure that I connect with this spider the name of my most kind friend and brother arachnologist, Monsieur Eugène Simon, to whom I am so greatly indebted for much information and numerous examples of rare spiders. I must not conclude these descriptions without expressing my sense of obligation to Mr. Moggridge for so kindly allowing me to add them to the far more popular, and more interesting, portion of this volume, in which the _habits_ of these spiders are recorded. Descriptions of _colour_, _form_, and _structure_ are but dry details, though very necessary for the determination of species; and in the present case it is very important as well as interesting to be able to conclude with some certainty that differences of type in the tubular nests of the spiders Mr. Moggridge has observed so closely and accurately, are joined to well-marked specific differences obtained from those other characters above mentioned, and which it has been my endeavour to detail as fully and faithfully as possible. INDEX TO SUPPLEMENT. PART I.--HARVESTING ANTS. Alyssocarpus, seeds of, collected by ants, 175 Amphisbæna, found in nests of Lauba ants, 177 _André_ (M. Ernest), on number of species of ants found in Europe, 160 (note) _Arabia_, custom in, relative to ants, 176 Atta, species of, found in Europe, 160 (note); _barbara_, 158; found in Palestine, 165; _megacephala_, 160; _structor_, 158; experiment with, 172; found harvesting at Cadenabbia, 159 _Cadenabbia_, harvesting ants at, 159 Camponotus _sylvatica_, 178 Cicendela, capturing ants, 164 Coluocera _attæ_, found in ants' nests, 177