Gill-slits sentence example
- In 1865 Kowalevsky discovered that the organs of respiration consist of numerous pairs of gill-slits leading from the digestive canal through the thickness of the body-wall to the exterior.
- In 1883-1886 Bateson showed by his embryological researches that the Enteropneusta exhibit chordate (vertebrate) affinities in respect of the coelomic, skeletal and nervous systems as well as in regard to the respiratory system, and, further, that the gill-slits are formed upon a plan similar to that of the gillslits of Amphioxus, being subdivided by tongue-bars which depend from the dorsal borders of the slits.
- The possession of gill-slits is as interesting a feature in the organization of Balanoglossus as is the presence of tracheae in Peripatus.
- These gill-slits occupy a variable extent of the anterior portion of the trunk, commencing immediately behind the collartrunk septum.
- There are, therefore, as many gill-pouches as there are gill-slits and as many gill-pores as pouches.Advertisement
- The ventral and lateral parts of the anterior margin of the collar constitute the so-called operculum (op.), a structure which not only acts as a lower lip, but must be important in separating the food-current produced by the cilia of the tentacles from the external apertures of the collar-canals and gill-slits.