. Bulletin - United States National Museum. Science. 146 BULLETIN 93^ UNITED STATES NATIONAL MUSEUM and sixteenth segments of cirrus v). There are also some spines along the distal sutures of the segments of the outer ramus of cirrus vi (;).^ The penis is very long, over 20 mm., purplish, densely and conspic- uously annulated, with a very few short hairs near the end. There is a blunt projection on the dorsal base. A paratype of apertus examined has numerous simple bifid and trifid spinules on the segments of cirrus iii, also a band formed of several rows of minute, flat, fimbriated
. Bulletin - United States National Museum. Science. 146 BULLETIN 93^ UNITED STATES NATIONAL MUSEUM and sixteenth segments of cirrus v). There are also some spines along the distal sutures of the segments of the outer ramus of cirrus vi (;).^ The penis is very long, over 20 mm., purplish, densely and conspic- uously annulated, with a very few short hairs near the end. There is a blunt projection on the dorsal base. A paratype of apertus examined has numerous simple bifid and trifid spinules on the segments of cirrus iii, also a band formed of several rows of minute, flat, fimbriated spines on the distal borders of the segments. Cirrus iv has a row of sutural spinules, but none. Fig. 42.—Balanus rostratus apertus (Cat. No. 38667). a, 1st cirrus, h, mandible. V, maxilla, d, 15th and 16th segments of cirrus \. were seen on vi. The palpi are similar in structure to those of B. balanus, except that the bristles are all very much smaller and shorter. Typical B. r. apertus is readily distinguishable from typical B. rostratus by the thinner wall, cylindric form, with large orifice, the wider, not sunken radii, and esi^ecially by having more tubes in the parietes, about 18 in the rosti-um, without transverse septa in the lower part, against about 14 in B. rostratus, where the septa extend close to the base. The tergum is narrower for its length, and, while usually white, it sometimes has a beautiful pink (vina- ceous) tint, which also colors the apices of the scuta in some of the specimens taken by Dall at Unalaska. The only tangible dif- ferences between the appendages of this form and B. halanus is that the number of spines on the segments of the cirri is greater in B. r. apertus^ and the penis is decidedly 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 United States National Museu
Size: 1846px × 1354px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorun, bookcentury1800, bookdecade1870, booksubjectscience
