LOUSE (Heb. כִּנָּם ,כִּנִּים in plural. Talmud כִּנָּה, singular), insect; one of the ten plagues with which Egypt was smitten (Ex. 8:13–14; Ps. 105:31) was the plague of lice. The כֵּן in Isaiah (51.6): "They that dwell therein shall die kemokhen" may refer to the louse; i.e., "like a louse." The louse caused much suffering to people of all classes in former times. A distinction was made between the dark-colored head louse and the light-colored clothes louse (Pes. 112b), two strains of the Pediculus hominis, against which people sought to protect themselves by constantly changing and washing their clothes – although they were also compelled to search their garments to kill the lice (Tosef., Shab. 16:21, where the louse is called ma'akholet, i.e., the eater). Lice nits were regarded as the smallest of creatures, and hence the statement that "the Holy One blessed be He feeds the whole world, from the horned buffalo to the lice nits" (Av. Zar. 3b). Some maintained that "the louse does not multiply and increase" (Shab. 107b) but generates spontaneously.
Lewysohn, Zool, 324–6; J. Feliks, The Animal World of the Bible (1962), 131.