Studies on ciliates of the family Ancistrocomidae Chatton and Lwoff (order Holotricha, suborder Thigmotricha). III. Ancistrocoma pelseneeri Chatton & Lwoff, Ancistrocoma dissimilis sp. nov., and Hypocomagalma pholadidis sp. nov. Biological Bulletin Wood's Hole, 91 1946: pp. 189-199. [Zoological Record Volume 83]