. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. io6 ANNALS OF THE SOUTH AFRICAN MUSEUM In a consideration of the origins of a group it is often difficult to decide which characters are primitive and which are advanced. Table 8 gives what I consider to be the primitive condition for twenty characters which have been used in my study. In some cases the definition of the primitive condition is based on the statements of Hubbs (19536) regarding typically clinid characters, and in others on the conditions prevailing in the genus Gibbonsia. Of the two s
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. io6 ANNALS OF THE SOUTH AFRICAN MUSEUM In a consideration of the origins of a group it is often difficult to decide which characters are primitive and which are advanced. Table 8 gives what I consider to be the primitive condition for twenty characters which have been used in my study. In some cases the definition of the primitive condition is based on the statements of Hubbs (19536) regarding typically clinid characters, and in others on the conditions prevailing in the genus Gibbonsia. Of the two subtribes of Clinini represented in South Africa, the Clinidi have by far the greatest representation, with five genera and 30 species in South African waters. The genera apparently represent two major lines of evolution and three minor ones. The hypothetical intergeneric relationships are shown in figure 45. The method used for devising the figure is similar to that used by Stephens (1963). The lateral position is based purely on morphological resemblance and the horizontal distances are arbitrary, but the vertical position indicates the 'primitiveness' of the genera. The 'primitiveness' is determined by the number of points awarded for each of the twenty characters listed in table 8, from no points for the 'primitive' condition of a character up to ten points for an 'advanced' condition. The thickness of the lines indicates the relative number of species. 100 90 80 70 60 SO 40- 30 201 10" 0. Fig. 46. Hypothetical interspecific relationships of the South African genus Clinus. The two major lines, leading to the genera Clinus and Pavoclinus, retain a fairly high number of 'primitive' characters, but these are not the same in the two groups; for instance, the supraorbital tentacle is retained in Clinus but lost in Pavoclinus, whereas the 'primitive' arrangement of the anterior dorsal spines for this group is retained in several of the species of Pavoclinus, but in none of th
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectnaturalhistory, booky
