76 



regular Crystallomia bract. On the stem there are indications of bracts which have become 

 detached through the contraction of the stem by preservation. 



The nectosome gets more lengthened, as is the case in Cat. 215 L., where its length 

 amounts to 4'/^ mm.; there one sees muscular bands, the indication of detached mature 

 nectophores. 



Cat. 25 B. is interesting since it forms the transition between the specimens which are 

 much larger and it shows besides the primar\' siphon with tentilla type I, a second one with 

 tentilla type III and IV and a third one whose tentilla are not \et differentiated. 



Cat. i§i D., jyjD., 175 C. stand almost at the same height of development. They are 

 larger; mature nectophores and bracts have unfortunately been detached, the muscular remnants 

 both on siphosome and nectosome showing the place where they were united to the stem. 



In all the above-mentioned specimens the reproductive organs were invisible. A very 

 small female gono.style is to be seen at the base of the third siphon in Cat. 25 A. The necto- 

 some in this specimen (PI. XII, fig. 92) measures 8 mm. in length; no mature nectophores have 

 remained on the nectosome. 



In all the Catalogue-numbers above mentioned there were always more developed 

 or quite mature bracts which show the same shape as those described b)- other authors in 

 Crysiallotnia. 



Cat. SS E. and 2^ A. show very beautiful purple-coloured pigment in the upper part of 

 the pneumatophore, some distinct mature bracts and a small Q gonodendron near the base of 

 the third siphon. The 9 gonophores are clearly distinguished in Cat. 25 A. 



No specimen in which one sees the development of the fourth siphon first without distinct 

 tentilla, then with its definite ones, was found in the Siboga material. 



Of all the specimens of this first group of Crystallomia, Cat. SS F. is assuredly the 

 most complete. 



The pneumatophore has purple-pigment at its top ; no mature nectophores are left, they 

 have all dropped off; the siphosome consists of 5 siphons, the primary with tentilla type I, the 

 2"'', 3'', 4''> and 5"^ with tentilla type III and IV. The three last siphons show gono.styles, which 

 are already elegantly botryoidal. The youngest 9 gonostyle is, of course, situated near the base 

 of the third si])hon. We could not make a sketch of this specimen as through torsion of the 

 stem all the appendages had gone out more or less of their place, and because a few well- 

 developed bracts covered these entirely and made it more difficult to sketch the specimen. The 

 whole has a length of 15 mm. 



The ne.\t Cat. 88 M. (PI. XII, fig. 94) is smaller than 88 P"., as it onl_\- shows two distinct 

 siphons. Whilst however in 88 V . the primary siphon was absolutely normal in shape, it seems 

 that the same in 88 M. (PI. XII, fig. 94) is reduced in size and that even its tentilla type I 

 are not as ncM'mal as they ought to be. This, of course, may be quite accidental, but we rather 

 incline to think that the primary siphon with its tentilla I falls oft. All the following specimens 

 of the table lack the primary siphon and we suppose that S8 M. represents the intermediate 

 stage between those specimens which possess a primary siphon and those where the primary 

 siphon fails. 



