Comparison of North Pacific Polymastia. Table 3 provides comparisons of known north Pacific Polymastia with regard to their spicules, water depth and geographic ranges. The first four species were recorded from the NE Pacific (de Laubenfels 1936, Lambe 1895, this paper). The last seven species in the table occur in the NW Pacific (Koltun 1959, 1962, 1966, 1970a, 1970 b; Plotkin 2002; Tanita et al. 1989). The fistulae shape and size of multifistulate Polymastia from the north Pacific are compared in Table 4, and the appearance of preserved multifistulate Polymastia from the NW Pacific is shown in Fig. 6. All species known from the NE Pacific are multifistulate, therefore north Pacific species with only a single fistula (P. hispidissima Koltun 1966) were excluded from further consideration.
Species Source Exhalant Larger Shape of Fistulae Mean Size of Than Inhalant Fistulae (LxW at Fistulae base) (mm) 1 Described specimens had only one fistula per sponge
? No data