FIELD NATURALISTS' CLUB, 289 



Tityus androcottoides (Karsh) (PI. xxix. figs. 3-3b.) 



Isometrus americanus var androcottoides, Karsch, 

 Mithh Munch, ent, Ver. 1879, page 113. 



Isometrus androcottoides, Pocock, Ann. Mag. N. 

 Hist. (6) iv. page 57. 



The British Museum has received very many examples of this species 

 from Trinidad (Messrs. Hart and Broadway). It is common in British 

 Guiana (Brit. Mus., W. L. Sclater.) 



Although Dr. Karsch looked upon this scorpion merely as a variety of 

 T. americanus — an opinion in which he has been followed by Professor 

 Kraeplin — I think there can be little doubt of its distinctness. When 

 first I put forward this suggestion, I had only seen a few examples of the 

 form to which the name androcottoides would apply ; but during the past 

 three years the British Museum has received many others, all of which 

 justify the belief in the distinctness of androcottoides from americanus. Apart 

 from sexual characters which are very distinctive, this species may be 

 recognized from americanus, as from all the Antillean species of the genus, 

 by the fusion of the inferior keels of the posterior caudal segments. 



Tityus melanostictus, sp. n. (PL xxix. figs 4-4b.) 



Colour flavous or fulvous, fusco-maculate, the ocular tubercle and 

 anteocular portion of carapace fuscous, mesially flavous, the posterior 

 and lateral portions of this plate fusco-maculate and lineate ; each of the 

 tergites, except the last, furnished in front with a transverse row of fine 

 fuscous spots, the external spot on each side is situated on the very margin of 

 the plates, the median one is divided by a flavous spot marking the median 

 keel ; posteriorly the tergites are adorned with three fuscous spots, the 

 median of which is divided, like the spot in front of it, by a clear flavous 

 spot, and the two lateral ones are united by a fine fuscous line, which 

 marks the transverse granular ridge ; the last abdominal segment, above 

 and below, fusco-maculate ; the rest of the sternites concolorous ; the 

 upper surface of the tail mostly concolorous, sometimes obscurely fusco- 

 maculate, the lower surface of the first three segments mottled with 

 flavous, the fourth and fifth segments and the vesicle generally uniformly 

 infuscate or reddish brown ; palpi subfuscous, mottled with round clear 

 flavous spots above, the digits fuscous at the base, becoming gradually 

 pale distally ; legs externally fusco maculate. 



Female : The upper surface of the body subtly granular, the normal 

 keels not strong but visible ; the sterna, except the last, smooth, marked 

 with more or fewer large punctures ; the last subtly granular with black 

 keels. The tail about 5^ times as long as the carapace, subtly granular, 

 the keels visible but weak and subtly granular ; the first segment with 

 ten keels, the second with eight and a trace of the median lateral ; the 

 first segment a little wider than the fifth. The vesicle armed with an 

 acute tooth beneath the aculeus. 



The palpi with well-expressed granular keels, the intercarpal spaces 

 coriaceous ; the manus small, internally rounded and produced, normally 

 costate ; the costae scarcely distinctly granular; its width considerably less 

 than half the length of the movable digit and less than the width of the 

 brachium. The digits long and slender, contiguous, neither lobate nor 

 sinuate ; the movable digit about twice the length of the " hand back" and 

 furnished with 14 rows of teeth. 



The pectines shorter than the posterior coxae, furnished with 15-17 

 (usually 16) teeth ; the proximal lamella of the intermediate series pro- 

 duced internally into a rounded prominence. 



