Science / Biology / Gill Slits: Opening or clefts between the gill arches in fish. Water taken in by the mouth passes through the gill slits and bathes the gills. Also, rudimentary grooves in the neck region of embryos of air-breathing vertebrates such as humans; a characteristic of chordates.
Science / Spiders / Sigillum: (pl. sigilla) An impressed, sclerotized spot, often reddish-brown. Often present on the dorsal surface of the abdomen and marking points of internal muscle attachments. MORE
Science / Marine Biology / Gillnet: A net set upright in the water to catch fish by entangling their gills in its mesh. MORE