A dodecapodous pycnogonid

Abstract
DODEC0L0P0DA (p. 107), resembling Decolopoda but possessing 6 instead of 5 trunk-somites, each bearing a pair of legs; based on D. mawsoni [male] (p.107), collected in the Antarctic (Lat. 66[degree] 45[image] S., 62[degree] 03[image] E.). It is suggested that the 10-legged and 12-legged Pycnogonida originated by the development of instability in the metameric pattern of octopodous forms; also that the Pycnogonida as a whole may owe their origin to an analogous disturbance of the cephalic metamerism of normal Arachnida. Broili''s Palaeopantopus from the Lower Devonian is discussed and reasons are given for suspending judgment as to its pycnogonid affinities. Palaeoisopus from the same formation shows no indication of affinities with the Pycnogonida.

This publication has 1 reference indexed in Scilit: