. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. 142 ANNALS OF THE SOUTH AFRICAN MUSEUM. Fig. I. Trachurus trachurus. Early larval stages showing pigmentation, pattern and position and degree of bone development. Measurements indicate standard length. A. 3,30 mm. B. 4,50 mm. C. 5,80 mm. D. 7,2 mm. bears four spines on the horizontal arm, the corner spine has become very long and there are two spines on the vertical arm. The number of spines laid down between this stage and 5,4 mm is usually the number that remains for the rest of the development. T
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. 142 ANNALS OF THE SOUTH AFRICAN MUSEUM. Fig. I. Trachurus trachurus. Early larval stages showing pigmentation, pattern and position and degree of bone development. Measurements indicate standard length. A. 3,30 mm. B. 4,50 mm. C. 5,80 mm. D. 7,2 mm. bears four spines on the horizontal arm, the corner spine has become very long and there are two spines on the vertical arm. The number of spines laid down between this stage and 5,4 mm is usually the number that remains for the rest of the development. There is a spiny ridge on the outer anterior edge of the preopercle with six to seven small spines on it. The cleithrum broadens very gradually and by 5,4 mm the supracleithrum has appeared as have the first traces of the opercle, the quadrate and the pterygoid. There are now seven branchiostegals. Between 5,4 mm and 6,6 mm further ossification takes place, all above-mentioned bones becoming heavier, darker and broader. New bones make their appearance, the frontal, sphenotic and parietal as well as the supra-occipital crest over the brain region. Laterally from this is the first indication of the pterotic and behind the pterotic. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original South African Museum. Cape Town : The Museum
Size: 1654px × 1510px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectnaturalhistory, booky
