ART. 4 SPONGES OF CALIFORNIA de LAUBENFELS 37 



Principle spicules, oxeas (fig. 15, F, G) ', size, ranging up to 22/x by 

 950/A. Ectosomal spicules, dichotriaenes (fig. 15, B, C) ; size of 

 rhabds, about 50/* by 400/*; size of clads, including the deuteroclads, 

 up to 50/1* by 310/x. First microscleres, bicurvate microstrongyles (fig. 

 15, ^) ; size 3/* by 50/* to 8/i by 160/*; a very few of the smallest ones 

 are faintly centrotylote. Second microscleres, oxyspherasters (fig. 

 15, /, J, K) ; total diameter, 9/t to 25/i, the smaller ones having the 

 more numerous rays. 



Remarks. — This species is very sharply set off by the peculiar 

 bicurvates. P. tyloaster Dendy, 1924, from New Zealand occasion- 

 ally has its dermal microscleres twice bent but they are oxea, not 

 strongyles, and the bicurvate form is rare; moreover the asters are 

 tylasters in that species. For further notes see the remarks under 

 Papyrula saccharis. 



Genus PAPYRULA O. Schmidt 



PAPYRULA SACCHARIS de Laubenfels 



Papyrula saccharis de Laubenfels, 1930, p. 26. 



Eolotype.—U.Q.^M. No. 21476 ; B.M. No. 29.8.22.5. 



Type locality. — Collected by me, at Point Pinos, Pacific Grove, 

 Calif., June 29, 1926. Found together with two smaller specimens, 

 lying loose under stones near low-tide mark. 



Descriptian. — Shape, massive, rounded. Size, up to 1.5 by 1.5 by 

 3.5 cm. Consistency, cartilaginous. Color in life and when pre- 

 served, white. Oscules, round, with depressed, rounded edges, di- 

 ameter about 200/t. Pores, of various sizes; some are 65/* to 150/i 

 and perhaps larger. Many openings can not be identified as to 

 whether they are pores or oscules. Surface, superficially smooth. 



Ectosomal specialization, a densely felted mass of microxeas, con- 

 taining also the cladomes of the dichotriaenes ; thickness about 100/*. 

 This is not easily detachable. Endosomal structure, " crumb-of- 

 bread," with spicules not very evident ; there is much solid matter as 

 compared to cavity. Histological details: The flagellate chambers 

 are spherical, about 30/t in diameter. There are very definite radiat- 

 ing fascicular tracts of diactines; total tract diam.eter, about lOO/i. 



Principal spicules, oxeas (fig. 16, E,F,G) ; size ranging up to 22/i 

 by 780/*; some are modified as styles. Ectosomal spicules, dichotri- 

 aenes (fig. 16, B, Cj D) ; size of clads, 10/* by 120/* to 30/i by 210/*, 

 size of rhabds, 20/x by 320/i to 30/* by 435/*. Microscleres, microxeas 

 (fig. 16, A) ', size, 1/* by 35/* to 3/c by 145/i; a very few are micro- 

 strongyles and some are bent once or twice; very rarely they are 

 centrotylote. 



