AFEICAN DIPLOPODA OF THE FAMILY GOMPHODESMIDyE. By O. F. Cook, Custodian of Myriapoda. The GomphodesiTiida' constitute a clearly defined and homogeneous group. They are apparently the dominant Meroeheta of tropical East Africa, with reference both to individuals and species, the Oxydesmidie being their only rivals. The Gomphodesmida^ are clearly a more si)ecial-i/ed group than the Oxydesmida' and, indeed, present several charac-ters unicpie in the order. Thtj first six legs of males, for instance, are provided at the end of the last joint with a fleshy pad or sole, present in all known species. In several genera the number of olfaetory cones of the last antennal joint is 10, while 4 is the normal and constant num-ber for all other known Merocheta. In some forms segment 15 bears iu males a subtriaugular process from between the anterior pair of legs; such a modification of the sternum of a single segnu'nt of the posterior part of the body is elsewhere unknown in the l)ii)lopo(la. Several other ecjually peculiar but not entirely unparalleled secondary sexual characters are described under the various genera. In habit the Gomphodesmida' are also strikingly distinct from all African Merocheta, the salient features being a robust and compact body, a strongly convex, unsculptiiriMl dorsum, lateral carina* with prominent, thickened, even, and entire lateial margins, the posterior segments greatly shortened, especially segment 18, with the last seg-ment short, broadly triangular, narrowly truncatt^ at apex and without prominent setiferous tubercles. The presence of pores on segments 11 and 14 will also serve as a means of family diagnosis, with the single exception of the genus Marptodesmus. An agreement in pore formula has led previous writers to refer the members of this family to the genus Eurydesmus Saussure,' a very imi)erfectly known genus supposed to come from South Amerit;a. Probably related Brazilian forms belong to a series which has been ' Essai Xlyr, Mex.— Mem. Soc. Phys. et Hist. Nat. Geneve, 1860, XV, p. 77. The type is E. angulaiue Saussure, idem, p. 78, supposed to be from Brazil. Proceedings U. S." National Museum, Vol. XXI— No. 1 1 70. (>77
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