IN THE LOWER XERTIAKY SXBATA OF NEW ZEAJjAND. 213 



very dissimilar from those of Melonancliora, and several recent 

 species of the genus are found in the Australian and South 

 Seas. 



Ancliorate JFlesh- Spicules of Gruitarra, Carter. 



Guitarra Carteri, n. sp. — Pi. XI. figs. 1, 2, 3. Spicules of hour- 

 glass form, consisting of two equal subcircular plates in contact 

 with each other. The shaft is not often disfciaguishable ; it is, as 

 shown in fig. 3, straight and of an even thickness. Usually it is so 

 amalgamated with the lateral portions of the circular plates that 

 it cannot be recognized. The plates bounding it represent the 

 lateral palms of the spicule. The central tubercles are circular 

 in outline and prominent ; they are connected by the axial canal, 

 which appears as a fine thread between them (fig. 2). The an- 

 terior palms are circular plates of a similar form and size to the 

 lateral plates, and as they meet in the central line they cannot 

 be distinguished from these latter when the front of the spicule 

 ■is exposed to view. The margin of the lateral palms is transversely 

 striated, and the outer surface of the anterior palm has also on 

 iboth sides a series of fine transverse markings which reach nearly 

 to the centre (fig. 1). Length of spicules from "09 to '115 mm., 

 width "05 mm. These spicules are much larger than those of the 

 •only known recent species, and further diff'erent in having the 

 anterior palms meeting in the centre. As indicating a new species 

 they may be named G-uitarra Carteri, in honour of Mr. H. J, 

 ■Carter, P.E.S. 



Guitarra intermedia, n. sp. — PL XL figs. 4-7. Spicules of hour- 

 glass form, but having the lateral palms at either end connected 

 by a constricted interspace (fig. 4), the tubercles distinct and 

 connected by the axial canal. The anterior palm is ovoid in form 

 with definite incurved margins ; it extends either obliquely to the 

 shaft (fig. 5) or nearly parallel with it, but the palms do not meet 

 as in the preceding form. The outer surface of the lateral palms 

 is minutely spined and the margins are striated. These spicules 

 range in length from '065 to '115 mm., and they are about 

 •045 mm. iu width. An apparently young form (fig. 7), which is 

 magnified on the scale of 600 diameters, is only '04 mm. in length. 

 In fig. 4 the front surface of a spicule is shown in which the 

 anterior palms have been broken away ; fig. 5 is an oblique view 

 of another form showing clearly the margins of the palms ; fig. 6 

 is a lateral view in which the front margins of the anterior palms 



