FREE BOOKS

Author's List




PREV.   NEXT  
|<   108   109   110   111   112   113   114   115   116   117   118   119   120   121   122   123   124   125   126   127   128   129   130   131   132  
133   134   135   136   137   138   139   140   141   142   143   144   145   146   147   148   149   150   151   152   153   154   155   156   157   >>   >|  
ongitudinal row; dorsal tufts, with four or five long spines. The second cirrus has its anterior ramus not thicker, but rather shorter than the posterior ramus; the former is only a little more thickly clothed with spines, owing to those in the longitudinal lateral row being longer and more numerous, than is the sixth pair of cirri. Bristles not serrated. _Caudal Appendages_, narrow, thin, slightly curved, about half as long as the pedicels of the sixth cirrus; in young specimens, the appendage bore seven or eight pair of long bristles rectangularly projecting; in some older specimens, there was a tuft of bristles on the summit, and two other tufts on the sides. I at first thought that the Borneo specimen was a distinct species, but after careful comparison of the external and internal parts, the only difference which I can detect is, that the terga are slightly larger, and that the carina, to a more evident degree, is wider, more especially in the middle and lower portions. 2. DICHELASPIS GRAYII. Pl. II, fig. 9. _D. scutorum segmento basali angustiore quam segmentum occludens; longitudine paene dimidia: tergis bipenniformibus, margine crenato, spina postica, manubrio angustiore quam occludens scutorum segmentum._ Scuta, with the basal segment narrower than the occludent segment, and about half as long as it. Terga like a battle-axe, with the edge crenated and a spike behind; the handle narrower than the occludent segment of the scuta. Mandibles with three teeth; cirri unknown. Attached to the skin of a sea-snake, believed to have been the _Hydeus_ or _Pelamis bicolor_, and therefore from the Tropical, Indian or Pacific Oceans; associated with the _Conchoderma Hunteri_; single specimen, in a very bad condition, in the Royal College of Surgeons. _General Appearance._--Capitulum much compressed, elongated, formed of very thin membrane, with the valves forming round it a mere border. Valves thin, imperfectly calcified, covered with membrane. _Scuta_ formed of two narrow plates at very nearly right-angles to each other, one extending along the occludent, and the other along the basal margin; both become very narrow at the point of junction, and are there not calcified, but are evidently continuous and form part of the same valve; the basal segment is about half as long and narrower than the occludent segment, flat and bluntly pointed at the end; occludent segment slightly curled, an
PREV.   NEXT  
|<   108   109   110   111   112   113   114   115   116   117   118   119   120   121   122   123   124   125   126   127   128   129   130   131   132  
133   134   135   136   137   138   139   140   141   142   143   144   145   146   147   148   149   150   151   152   153   154   155   156   157   >>   >|  



Top keywords:

segment

 

occludent

 
slightly
 

narrow

 

narrower

 
angustiore
 

scutorum

 

segmentum

 

occludens

 

calcified


membrane

 

formed

 
specimen
 

specimens

 
bristles
 
spines
 
cirrus
 

believed

 

Attached

 

unknown


Hydeus

 

Tropical

 
Indian
 

Pelamis

 

bicolor

 

handle

 
battle
 

curled

 

pointed

 

bluntly


Pacific

 

Mandibles

 

crenated

 

Hunteri

 

valves

 

forming

 

extending

 
margin
 

compressed

 

elongated


border

 

imperfectly

 
covered
 
Valves
 

angles

 

Capitulum

 

condition

 
single
 

Conchoderma

 

plates