REPORT ON THE CRUSTACEA MACRTJRA. 475 



anteriorly considerably beyond the lateral angles, and covers about half the pereion, so 

 that, when viewed dorsally, it appears triradiate, or shaped somewhat like an arrow-head. 

 The somites of the pleon * are subequal, gradually lessening in length and breadth pos- 

 teriorly to the fifth somite, which is slightly longer than the preceding and produced 

 in the form of a blunt tooth on each side at the postero-lateral angles. The sixth somite 

 is a little longer than the preceding and is produced to projecting angles at the postero- 

 lateral extremity. The telson is a little longer than the sixth somite, gradually increases 

 in width posteriorly, and terminates at each angle in a long tooth-like process, the base 

 on the outer side being furnished with two small teeth or spines, and on the inner with 

 five long blunt spines on each side of the median line. 



The ophthalmopoda are large, gradually increasing in diameter from the base to the 

 ophthalmus, the peduncle being slightly curved backwards and is longer on the posterior 

 than on the anterior margin. 



The first pair of antennas has the peduncle obscurely divided into three joints, of 

 which the first is short and the others subequal, and terminally supports two very 

 short flagella. 



The second pair of antennas has the flagellum short, and is furnished with a scapho- 

 cerite that gradually tapers to a sharp point, and reaches nearly as far as the apex of the 

 rostrum. It is curved, smooth and rigid on the outer margin and fringed with distantly 

 planted hairs on the inner. 



The oral appendages have not been examined. 



The pereiopoda, which are short and curved inwards, are in an immature condition ; 

 the first pair is the largest and subequal and chelate. 



The pleopoda are small and biramose but not fully developed. The sixth or posterior 

 pair is furthest advanced but has the rami unequal, the inner branch short and bud-like, 

 the outer long, styliform, and fringed with hairs on the inner margin. 



Observation. — The serrature on each side of the postero-lateral angle of the carapace, 

 although not quite similar, is yet suggestive of that in the Zoea form of Galathea ; hence 

 the specific name. 



Zoontocans approximus, n. sp. (PI. LXXXV. fig. 4). 



Pereion globose. Carapace anteriorly produced to a sharp-pointed rostrum, broad at 

 the base and fringed with small spines ; posteriorly produced at each lateral angle to a 

 long and slender tooth, smooth at the base. Pleon narrow, fifth somite armed on 

 each side with a tooth at the postero-lateral angles. Telson broad and terminating 

 posteriorly in sharp-pointed lateral angles. 



Ophthalmopoda long, ophthalmus large. 



1 I have erroneously figured the pleon with a somite too few ; the lobe shown as the pereion should be divided. 



