272 PART II. SYSTEMATIC ACCOUNT 



distally. The pinnules, which are numerous and rather long (80/x), are 

 arranged in two double rows and give the tentacle a bushy appearance 

 (Fig. B133#,7). The cephalic lobe of the protosoma is rather small and there 

 is no pretentacular groove. There is a complete but shallow groove around 

 the body just behind the base of the tentacle, and this is the only groove in 

 front of the bridle. The bridle consists only of the narrow keels, but these are 

 pale yellow and easier to see than those of S. weberi (Fig. ЪХЪЪА, В). The 

 keels join together to form points on both sides of the body (except in one 

 specimen where there is a small gap between their ends on the dorsal side). 

 The fore-part of the body is usually 0-6 to IT mm long. The diameter of the 

 mesosoma is 0-09 to ОТ 1 mm and is thus one-sixth to one-tenth of the length 

 of the whole fore-part. 



"The metameric papillae are not very well marked ; they form two slight 

 ridges each containing a single row of 40 to 50 pyriform glands, and extend 

 for about 2 mm. Behind the metameric region the trunk is smooth until just 

 before the girdles, where there is a row of at least three papillae crowned with 

 fine, curved, cuticular bars about lOju. long. The preannular region is 14 to 

 26 mm long and the three girdles extend over at least 1 mm. The first and 

 second girdles lie close together and are made up of rather irregular single 

 rows of platelets, while the third lies 1-0 to 1-5 mm behind the second and is 

 more regular (Fig. В 133 К, L). The platelets are 10 to 12/x long and have two 

 approximately equal groups of teeth. The postannular region is up to 12 mm 

 long but no papillae have been seen on it. 



"Spermatophores are present in six of the specimens examined; they 

 are relatively large for such a small species — 120 to 190/* long and 25 to 30/x 

 in diameter. 



"The tubes of this species are easily confused with those of S. weberi, 

 being much the same diameter and colour. The longest tube (broken) is 

 5-5 cm long. The diameter of different tubes varies from 0-10 to 0-135 mm 

 and the majority are slightly larger than the majority of S. weberi. The tube 

 walls are thin and smooth, and for the first few mm they are limp and colour- 

 less. This colourless part and at least some of the rest of the tube is marked 

 into segments by occasional wrinkled rings, as in S. ekmani Jagersten (1956). 

 Most of the tube is ringed, first with rather narrow brown rings which 

 become gradually wider. Here the segments are 6-7 rings long. Farther 

 back the rings are divided to form double rings, as in S. weberi, and at the 

 posterior end there is a complex pattern of narrow yellow rings (Fig. 

 B133C-C). 



"S. macrobrachium is rather similar to S. buccelliferwn Ivanov, which was 



