. Bulletin - United States National Museum. Science. vou 2, it. 2.] A TAX0N0MIC STUDY OP THE SALPIDAE METCALF. 125 (pi. 14), even in the peculiar appearance of the enlarged tips of the inner tubes. Protuberances of the test at the posterior angles of the body are found in numerous species, and in many of these species they contain tubes whose epithelial lining is continuous with the mantle. The gut is a round coil which may be called a "nucleus," though it is less densely compacted than in the Apsteinias and Salpas. One can make out the course of the intestine without dissection. I h
. Bulletin - United States National Museum. Science. vou 2, it. 2.] A TAX0N0MIC STUDY OP THE SALPIDAE METCALF. 125 (pi. 14), even in the peculiar appearance of the enlarged tips of the inner tubes. Protuberances of the test at the posterior angles of the body are found in numerous species, and in many of these species they contain tubes whose epithelial lining is continuous with the mantle. The gut is a round coil which may be called a "nucleus," though it is less densely compacted than in the Apsteinias and Salpas. One can make out the course of the intestine without dissection. I have not had sufficient material to study the histology of the neural organs and gland. Examination of total preparations shows the eye to be of the usual horseshoe form. THETYS VAGINA, aggregated form. There are five body muscles (fig. 117), all narrowly interrupted dorsally and extending laterally only to the sides of the body. The ventral half of the body has no muscles of any sort. The fifth body ,rb. FlQ. 117.—THETYS VAGINA, AGGREGATED ZOOlD VIEWED FROM THE RIGHT SIDE, I NATURAL SIZE. (Drawn by Hoyt S. Hopkins.) muscle is divided on each side into an anterior and a posterior branch, as in the aggregated forms of other species, but the posterior branches are short and do not pass below the atrial siphon or give rise to any visceral muscle. The intermediate muscle is as in the larger of my specimens of the solitary form of this species, not being fused with the rudimen- tary first sphincter of the upper lip. The oral musculature, includ- ing the horizontal dorsal band, is like that of the solitary form, except that there are three, instead of two, dorsal sphincters, the first very short and very slender, the second also very short. The musculature of the atrial siphon, also, is like that of the solitary form, except that there are 12 to 15, instead of 11, sphincters in my specimens. On the dorsal side the basal sphincter is widely inter- rupted in the middle, and ventral
Size: 2415px × 1035px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorun, bookcentury1800, bookdecade1870, booksubjectscience
