. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. THE ANATOMY OF THE CAPE ROCK LOBSTER 193 (1952) has concluded that they cannot be accepted as indications of adaptive modifications, they are, nevertheless, of interest in a consideration of the eyes oi Jasus. Compared \vith the pueruhis stage, the ommatidia of the adult eye have proportionally longer cone stalks, but this may be merely a normal incident in the transformation of the larva into the adult state, for Kampa, Abbott & Boden (1963) have observed that a similar elongation of the cone st
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. THE ANATOMY OF THE CAPE ROCK LOBSTER 193 (1952) has concluded that they cannot be accepted as indications of adaptive modifications, they are, nevertheless, of interest in a consideration of the eyes oi Jasus. Compared \vith the pueruhis stage, the ommatidia of the adult eye have proportionally longer cone stalks, but this may be merely a normal incident in the transformation of the larva into the adult state, for Kampa, Abbott & Boden (1963) have observed that a similar elongation of the cone stalks takes place between the zoaea and the adult stages of Homarus gammarus [vulgaris). A more remarkable difference in J. lalandii is the apparent structural resem- blance of the short rhabdomes of the adult eye to those of deep-sea Penaeidae examined by Ramadan (1952). While Parker (1891) was somewhat doubtful as to the presence of rhabdomes in Palitiunis (probably Panulirus), Exner (1891) remarked that the eyes of Palinurus may be compared to those of Palaemon and Sicyonia, but that 'die Sehstabe sind hier ziemlich klein' (p. 124). In sectioned material of the eye of J^. lalandii, differentially stained with Heidenhain's iron and phloxine, the rhabdomes are visible as short, clear, cerise structures which are sharply contrasted with the surrounding, narrow, heavily- pigmented retinular cells. The latter are uniformly constructed throughout their length, and in distal transverse sections (fig. 73) they are disposed around the rhabdome, but this is quite unlike the striated, fusiform structure observed retinular cells. Fig. 73. Transverse section of rhabdomes of adult eye. in the puerulus ommatidium. It is composed of seven branched rays which correspond with the seven main retinular cells, and in dissections of bleached preparations superficially resemble the curved staves of a minute barrel. Proximally the rhabdome appears to taper off, but the rosette formatio
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectnaturalhistory, booky
