Talmud for Menachot 79:15

As regards a [linen] sheer, Beth Shammai exempt it [from zizith],⁴Because woollen zizith in a linen garment are forbidden as mingled stuff, wool and linen together (Deut. 22, 11). but Beth Hillel declare it liable.⁵In their view the prohibition of wearing mingled stuff is superseded by the commandment of zizith, since the prohibition in Deut. is immediately followed (in verse 12) by the commandment of twisted cords or zizith. The juxtaposition of the two commandments indicates that the latter supersedes the former. An undergarment is exempt, but R. ‘Aḳiba holds that it is liable. A [double-sized] ṭallith that is folded over is subject to zizith, but R. Simeon exempts it.⁶Since if it should happen to be unfolded, the zizith would not be in their proper place, in the four corners, but in the middle of the sheet. A ṭallith consisting entirely of blue wool is subject to zizith.⁷The blue texture of the ṭallith does not exempt it from zizith although one thread of blue (Num. 25, 39) in each of the four zizith is sufficient. A bolster converted into a sheet or a sheet converted into a ṭallith is subject to zizith. A night garment and bed-curtains⁸Or, ‘covers’. are exempt from zizith.⁹In the commandment it is stated, That ye may look upon it (ibid.), which rules out garments worn during the night. A toga,¹⁰Reading ṭoga’ with Jastrow. V has ṭrigon which means ‘a triangular [cloak]’. [It was oval in shape and therefore did not require zizith; cf. Krauss, Talmudische Archäologie, I, p. 611, n. 589.] a travelling cloak,¹¹In V pilgas which Jastrow emends to pinolës (the Greek phainoles). [It is the paenula worn by Roman slaves; Krauss, op. cit. I, p. 170.] shawls fastened at the shoulder,¹²In V pokaltorin, which Jastrow reads as pibolaṭorin, the Latin fibulatorium. a cloak worn on the head,¹³In V ’arbiḳwah. [Krauss loc. cit. identifies it with saga Nervica, a garment of various materials and in different colours.) and an ’anṭenah¹⁴According to Jastrow possibly a corruption of the Greek tebenna, a kind of Roman toga. are exempt. This is the general rule: Any [garment] that is without four corners is exempt from zizith.