Fig.3. Mastigograptus aff. tenuiramosus. A in The ultrastructure, development, and systematic position of the graptolite genus Mastigograptus

Fig.3. Mastigograptus aff. tenuiramosus. A.Stipewiththickcortexandfracturedthecalbase.(ZPALG.30/4).Scalebar100µm. B.Occludedthecalbaseon proximal portion of stem (ZPALG.30/3). Scale bar 10 µm. C. Proximal portion of stem, with occluded sicula and first thecal base. (ZPALG.30/2). Scale bar 200 µm. D. Portion of stem with monopodial branch (ZPALG.30/5). Scale bar 2 µm. E. Fractured stolotheca; distal to left (ZPALG.30/6). Scale bar 50 µm. F. Fractured stem with thick cortex and borings (ZPALG.30/7). Scale bar 50 µm. G. Amphorate stolothecae, and broken thecal bases (ZPALG.30/4) Scale bar 1 mm. H. Amphorate stolotheca, looking proximally. (ZPAL G.30/8). Scale bar 100 µm. I. Stereopair view of thecal base (ZPAL G.30/4). Scale bar 100 µm.