Miscellaneous. 109 
The adult male presents the pleon characteristic of the male of 
 Phryxus, without pleopoda or uropoda. But the antenne and the 
rostrum strongly remind us of the structure of the Cryptoniscian 
embryos. 
The examination of Dajus renders that of Aspidophryaus much 
easier. The Aspidophryxus which has been entrusted to us by Mr. 
Norman had been determined as A. peltatus by G.O. Sars. But 
the type of Aspidophryxus peltatus described and figured by Sars is 
parasitic upon Hrythrops Goesi, and what we know of the vigorous 
specificity of the Epicarides to each definite host led us at once to 
regard the parasite of Hrythrops microphthalma as belonging to a 
distinct species. A minute comparison of this parasite with the 
figures given by G. O. Sars, which are so exact, appears to us to 
justify this supposition, and we shall give the name of Aspido- 
phrycus Sarsii to the Epicaride of Erythrops mtcrophthalma. 
This new species differs from Aspidophryaus peltatus (1) in the 
less widened and more slender general form of the female, (2) in 
the number and arrangement of the ova in the incubatory chamber. 
While in A. peltatus the ova are diffused in great numbers and 
without order in the incubatory cavity, in 4A. Sarsi they are 134 in 
number, arranged in regular concentric rows, each row containing 
respectively 17, 17, 15, 10,5, and 3 ova in one half of the body, 
between the free margin and the median line. These ova are more- 
over larger than those of A. peltatus. Further, the animal is less 
distinctly segmented. In the male, on the contrary, the segments 
of the pleon, although soldered together, are more distinct than in 
A, peltatus 
If we referred exclusively to the description and figures given by 
G. O. Sars, there would be much more considerable differences 
between the two species, and the genus Aspidophryxus would seem 
far removed from the genus Dajus. The complete absence of incu- 
batory lamelle in the female (laminew incubatorie nulle) and the 
existence of only sew pairs of thoracic feet in the male would con- 
stitute characters of great importance in this group of Epicarides. 
But we have ascertained that these characters were due to errors of 
observation. The incubatory lamelle all exist as in Dajus; the 
first four pairs are more reduced, in consequence of the approxima- 
tion of the thoracic feet to the anterior part of the body. Like the 
first pair in the other Bopyrians, they have only an accessory func- 
tion in the protection of the ova. As to the fifth lamelle, these are 
represented by a pair of narrow plates bordering the free edges of 
the greatly enlarged last thoracic somites; they terminate in digi- 
tations posteriorly. These plates are applied to each other exactly 
in the median line, and with the lateral ventral folds of the thoracic 
somites form the incubatory cavity properly so called. 
The pleon also presents considerable reductions compared with 
that of Dajus. It is completely destitute of appendages and forms 
a small cavity, in which is lodged the male, folded up like a Scara- 
ban larva and placed in profile. 
This male differs little from that of Dajus; the segments of 
