19 



PLATE IX. 



Bgionehia (lOMPiiESSA, Bowerhank. 



Vol. ii, p. 55, ' Mon. Brit. Spongiadss.' 



Fig. 1.— The type-specimen of E. compressa. Natu- 

 ral size. 



Fig. 2. — One of the skeleton spicula. X 80 linear. 



Fig. 3. — An attenuato-patento-ternate, connecting 

 spiculum of the normal form. X 80 hnear. 



Figs. 4, 5. — Two abnormal forms of the connecting- 

 spicula. X 80 linear. 



Fig. 6. — One of the inflato-acerate, incipiently- 

 spined, tension spicula. X 250 linear. 



Fig. 7. — An inflato-acerate, incipiently-spined, ten- 

 sion spiculum. X 250 hnear. This form is of com- 

 paratively rare occurrence. 



Figs. 8, 9.- — -Two of the largest attenuato-stellate, 

 retentive spicula, showing the variety that occurs in 

 the number of their radii. X 250 linear. 



Figs. 10, 11. — Two of the minute, elongo-attenuato- 

 stellate, retentive spicula, showing the variation in 

 their size. X 250 linear. 



Fig. 12. — A doliolate, cylindrical, retentive sjDiculnm. 

 X 250 linear. 



During a searching examination of the spicula for 

 figuring I found a few doliolate spicula very similar to 

 those in E. ponderosa. One of these I have figured, 

 and we must, therefore, add to the specific character 

 of the species under consideration in the description 

 of the spicula of the interstitial membranes " and 

 doliolate cylindrical spicula, few in number." 



