from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A bladder or wing-like structure found on the pollen grains of many species of conifer. The shape or number of the sacci on a pollen grain can help identify the species it came from.
from the GNU version of the Collaborative International Dictionary of English
- n. A sac.
from The Century Dictionary and Cyclopedia
- n. In anatomy and zoöl., a sac.
- n. [capitalized] In conchology, a genus of gastropods: same as Ampullaria.
- n. Synonyms See sac.
The hypothesis that lungfishes are the sister group of amphibians is supported by two possible synapomorphies: loss of a saccus vasculosus and the presence of neurocranial endolymphatic sacs.
Retzius has named it the eminentia saccularis, and regards it as a representative of the saccus vasculosus found in this situation in some of the lower vertebrates.
Where the saccus vaginalis remains patent throughout, the cavity of the tunica vaginalis communicates directly with that of the peritoneum.
There are some varieties of oblique inguinal hernia (Fig. 1084) depending upon congenital defects in the saccus vaginalis, the pouch of peritoneum which precedes the descent of the testis.
It is analogous to the saccus vaginalis, which precedes the descent of the testis.
From the posterior wall a canal, the ductus endolymphaticus, is given off; this duct is joined by the ductus utriculosaccularis, and then passes along the aquæductus vestibuli and ends in a blind pouch (saccus endolymphaticus) on the posterior surface of the petrous portion of the temporal bone, where it is in contact with the dura mater.
Just before birth the upper part of the saccus vaginalis usually becomes closed, and this obliteration extends gradually downward to within a short distance of the testis.
The testis thus acquires an indirect connection with the anterior abdominal wall; and at the same time a portion of the peritoneal cavity lateral to these fused folds is marked off as the future saccus vaginalis.
The one above the testis is the plica vascularis, and contains ultimately the internal spermatic vessels; the one below, the plica gubernatrix, contains the lower part of the gubernaculum, which has now grown into a thick cord; it ends below at the abdominal inguinal ring in a tube of peritoneum, the saccus vaginalis, which protrudes itself down the inguinal canal.
A pouch of peritoneum analogous to the saccus vaginalis in the male accompanies it along the inguinal canal: it is called the canal of Nuck.