302 DISCOVERY REPORTS 



in the other completely wanting. A strong crest runs from the dorsal organ to the base 

 of the rostral spine. The carapace has no posterior projection or, at most, a low blunt 

 projection shorter than the postero-lateral wings. 



The antennular spine may still be as long as the sum of the second and third segments 

 of the peduncle. The lappet of the basal segment is usually large and simple, its margin 

 not incised ; the beginnings of the carina of the third segment may be present. 



In some of the specimens the mandibular palp is unsegmented and non-setose; in 

 most it is of three segments and setose. 



The thoracic limbs of one of the specimens, 8-6 mm. long, are as follows: 



First limb. Endopod long and kneed. A very small gill bud. 



Second and third limbs. Endopods long and kneed. Gills of three roughly equal 

 branches. 



Fourth and fifth limbs. Endopods long and kneed. Gills of two large and one smaller 

 branch. 



Sixth limb. Endopod shorter, of five segments but not kneed. Gill of three large 

 branches and small buds of others. 



Seventh limb. A gill of four large branches and small buds. 



Eighth limb. A gill of four medium-sized branches and one small bud. 



The tergal wings of the first abdominal somite are becoming rectangular. The spine 

 of the third somite is very strong, longer or appreciably longer than the fourth somite. 

 There are as yet no spines on the fourth and fifth somites. The postero-lateral spines of 

 the sixth somite are still present but very short. The telson is narrow with one to three 

 pairs of lateral spines. Of the postero-lateral spines those of the innermost pair are 

 strong and wide, the middlemost are reduced, the outer very small. 



Post-Larval Stages 



In none of the specimens I have examined, nine from the present collection and nine 

 from the material described by Illig (see p. 294), is there any trace of the posterior pro- 

 jection of the carapace.! \^ jg retained by the earliest post-larval stages of E. longirostris. 



The nine specimens of this collection are of the following lengths : 



9-5 mm. ... ... I 10-6 mm. ... ... i 



lo-o „ 2 ii-o „ I 



10-2 „ I II-2 „ I 



10-5 ,, I 13-0 „ I 



Tattersall's single specimen was only 8-5 mm. long (Tattersall, 1924, p. 26). I found 

 one even smaller among Illig's material : it was only a little over 7 mm. and had a wide 

 frontal plate with rounded antero-lateral corners and no trace of a rostral spine. This 



1 Tattersall (1924, p. 26) says that his post-larval specimen "agrees closely with Ortmann's description 

 and figure of E. schotti" (Ortmann, 1893, pi. vii, fig. 8). But Ortmann's figure shows a strong posterior 

 projection on the carapace whereas Tattersall's post-larva, which I have been able to examine in the Natural 

 History Museum, has none. Ortmann's figure appears to be of a late, but not the last, Furcilia. 



