SPONGES, GRAPTOLITES, CORALS. 73 
Anomalospongia.] 
constriction of the vertical ray immediately beneath the horizontal rays. This is 
relatively greater in Anomalospongia than in any other form known to me, 
To resume: we have among the differences (1) the total absence of summit 
plates, (2) three instead of four horizontal spicular rays, (3) the duplex character, and 
(4) the interweaving of the horizontal rays, (5) the contact between the club-shaped 
vertical rays, and (6) the uniform size and different arrangement of the spicules. 
Opposed to these we have as points of agreement, (1) the form and comparatively 
large size of the vertical or entering ray, (2) its arrangement in the sponge-wall per- 
pendicular to the surface, and (3) the possession of relatively small horizontal rays. 
This concise statement of the points of likeness and of difference is I believe 
sufficient to show that Anomalospongia cannot be placed in the same family with 
Receptaculites. Still, 1 am satisfied that real relationship, however remote, exists 
between them. As I now view the matter it seems advisable to introduce a new 
order for the reception of the Receptaculitidw, Anomalospongia, and also Amphispongia, 
Salter ; the relations between the last two seeming to be, as I will endeavor to show 
presently, closer than might be suspected from a casual comparison. 
The new order would be strictly paleozoic, and, excepting a few forms that sur- 
vived into the Devonian and possibly later, would be essentially Silurian. It would 
therefore comprise only early types that, in common with nearly every class of 
animals represented in paleozoic times, may be called comprehensive because they 
_combine characters which in more recent times became separately developed and 
diagnostic of now widely different groups of genera and families. Perhaps the most 
striking diversity in these respects, shown by the forms in question, is the difference 
in the number of horizontal rays pertaining on the one hand to the Receptaculitide 
with four, and on the other to Anomalospongia with three. 
In the number and disposition of their rays the spicules of Anomalospongia 
remind us of true Tetractinellide. 'They also resemble, perhaps even more, the trifid 
surface spicules (“Gabel-Anker”) of many lithistid sponges. The horizontal rays in 
the latter often are bifurcate close to the centre, so that even the duplex character 
of these rays in Anomalospongia is in a measure simulated. (See fig. lb and.) I 
am not prepared to decide definitely that these resemblances are or are not indica- 
tive of relationship. It seemed desirable, however, to mention the facts, since they 
illustrate the sense of the preceding paragraph. 
As already indicated, it is my belief that the uncertain Amphispongia is related 
to Anomalospongia—indeed, that the two might well be united in one family. That 
genus was proposed by Salter* for certain free, compressed, elongate-elliptical masses, 
rounded at both ends, and rarely more than 50 mm. long by 18 mm. wide, which 
*Mem. Geol. Sur. Gt. Britain. 32, Scotland, p. 135, 1861. 
