THE HONEY-GUIDES 13 



united distally he apparently had an imperfectly cleaned skeleton 

 before him. As may be seen from our illustration, these two pro- 

 cesses are free terminally. The sternal notches (between the processus 

 lateralis posterior and the processus intermedins and the metasternum) 

 are relatively somewhat deeper in Prodotiscus and Melichneutes, and 

 shallower in Indicator (especially so in /. indicator and /. minor). 



The synsacrum varies less strikingly, but also reveals a few minor 

 characters of interest. Here it is essential to compare only specimens 

 of the same sex (see fig. 3). Again Prodotiscus deviates the most 

 from the main stem of the family; in it the acetabular process is 

 relatively much farther back, making the anterolateral margin of the 

 area dorsalis of the pars renalis of the ischium more steeply diagonal, 

 the linea iliolateralis relatively shorter, and the pars glutea of the 

 ilium longer and narrower than in the species of Indicator and Melich- 

 nevtes. The ilium is slightly longer, relatively, in Melichneutes than 

 in Indicator indicator. The pars glutea of the ilium is considerably 

 broader in Indicator xanthonotus than in any of the other species 

 examined, as may be seen from the diagrams; the anterior portion 

 of its synsacrum being thereby made almost as broad as the area 

 dorsalis of the ischium. The nearest approach to this characteristic 

 is found in Indicator maculatus. 



The coracoids of Melichneutes robustus have the sternocoracoidal 

 process much blunter than in Indicator variegatus (in which species 

 they are curved and pointed anterolaterally), agreeing in this respect 

 with /. indicator, I. exilis, and /. minor. 



The clavicles are ankylosed medioventrally in all the honey-guides, 

 forming a true furculum, but always lacking a hypocleidium. 



The description by Lowe (1946, p. 106) of the skull of /. indicator 

 is fully borne out by my own study of this species. The skull of I. 

 variegatus is similar, with the following slight differences: Anterior 

 ends of the vomers touch the prepalatines (considerable space between 

 them in I. indicator)] the posterior ends of the palatines are thinner 

 and the transition from this thinness to the broad flaring portion is 

 more abrupt and sudden; the maxillopalatines appear to meet in the 

 midline dorsal to the vomers; the pterygoids are more dilated anteri- 

 orly; the basioccipitals are somewhat convex ventrally and are divided 

 by a median groove (not indicated in Lowe's figure of I. indicator); 

 the whole skull is slightly broader posteriorly. In Indicator exilis the 

 vomers are bowed laterally more than in either 7. indicator or /. 



Figure 3. — The synsacrum in eight species of honey-guides, all drawn to same size: a, Indi- 

 cator variegatus, cf; b, Indicator indicator, cT; c, Indicator exilis, cT; d. Indicator xan- 

 thonotus, cf; e, Indicator maculatus, 9//, Indicator minor, 9/ g, Melichneutes robus- 

 tus, 9 ; h, Prodotiscus regulus, 9 • 



