FISHERY BULLETIN: VOL. 72, NO. 4 



The anal fin rays showed only slight staining. 

 The 14.0-mm specimen had 15 ossified dorsal 

 rays and pterygiophores; the anal had 11 un- 

 stained rays and pterygiophores. At this size, 

 the vertebrae were countable and the dorsal rays 

 were over the 24th to 29th vertebrae. The anal 

 fin was beneath the 34th to 38th vertebrae. In 

 the 14.9-mm specimen, 17 ossified dorsal rays 

 were present and were over the 20th to 27th 

 vertebrae. The anal fin had 15 faintly stained 

 rays and visible but unstained pterygiophores. 

 This fin was under the 33rd through 38th 

 vertebrae. In the 15.6-mm specimen, the anal 

 fin pterygiophores were well ossified. Seventeen 

 dorsal pterygiophores supported 18 rays (1 ptery- 

 giophore supported the first 2 rays), and 14 anal 

 pterygiophores supported 15 ossified anal rays 

 (1 pterygiophore supporting the first 2 rays). 

 In that specimen, the dorsal fin was over the 

 19th to 27th vertebrae, the anal under the 33rd 

 to 37th vertebrae. In the 16.4-mm specimen, 18 

 dorsal and 16 anal ossified rays were present. 

 The first few pterygiophores of each fin were 

 faintly stained. The dorsal fin was over the 18th 

 to 25th vertebrae, the anal under the 32nd to 

 38th vertebrae. In the 18.0-mm specimen, there 

 were two ural vertebrae in the caudal region. In 

 the 12.0-mm specimen, the middle vertebrae were 

 visible because the ventral portions of their centra 

 were ossified. In the 12.4-mm specimen, 20 verte- 

 brae anterior to the dorsal fin were ossified. 

 Neither the first few vertebrae nor the last several 

 were ossified. The 14.0-mm specimen had the first 

 vertebra faintly stained, the next 36 were com- 

 plete, the next 3 were visible but unstained, and 

 the last had only the lower half of the centrum 

 stained. In this specimen, a few neural arches near 

 the middle of the vertebral column were lightly 

 stained. The first 10 hemal spines also were 

 slightly stained as were the 2 preceding the 

 parhypural. In the 14.9-mm specimen, all neural 

 spines and hemal spines were lightly stained. 

 Pleural ribs were first observed in the 15.6-mm 

 specimen on the 8th to 16th vertebrae. From den- 

 sity of stain, it appears that they develop in a 

 posterior to anterior direction. 



completed for the related Atlantic thread herring, 

 Opisthonema oglinum (Richards et al., 1974). 

 The maxillaries and dentaries of scaled sardines 

 ossified at 11.5 mm. At this time, the maxillary 

 bore five small teeth. These teeth were too small 

 to be shown in the illustrations. Teeth were added 

 with growth — 8 teeth at 14.0 mm, 14 teeth at 

 14.9 mm, 17 teeth at 15.6 mm. Teeth were 

 observed on the dentary only on the 15.6-mm 

 specimen, where two were observed. Dentary 

 teeth apparently are a temporary feature. Teeth 

 also were present on the basihyal; the 15.6-mm 

 specimen had two large teeth, and the 16.6-mm 

 specimen had three teeth on this bone. These 

 teeth, like the dentary teeth, apparently are 

 temporary larval structures. They were also 

 seen as temporary structures in the larvae of 

 O. oglinum (Richards et al., 1974). The pre- 

 maxillaries were first visible in the 14.9-mm 

 specimen, and the posterior supramaxillaries 

 were first seen in the 16.6-mm specimen. The 

 anterior supramaxillaries and the hypomaxil- 

 laries had still not developed in our 19.3-mm 

 specimen but were present in our 22.4-mm speci- 

 men. Berry (1964a) reported hypomaxillaries to 

 be developed in a 16-mm specimen of Harengula 

 thrissina from the eastern Pacific. 



Pigmentation 



Melanophore distribution on preserved scaled 



/ / 



Head Bones 



The many skull bones were difficult to de- 

 scribe. A detailed analysis of general develop- 

 mental changes in skull development has been 



Figure 7. — Late stage egg o( Harengula jaguana. 



1116 



