sig til Ring- og Længdemusklerne.* 
Fra Schmardas Ilagttagelser afviger derimod vore 
temmelig betydeligt; thi hverken have vi fundet fibrillært 
Bindevæv, maskeformigt sammenvævet med Kar, eller Kjer- 
telorganer. Vi ere tilbøielige til at betragte saavel de 
enkelte, som de i Grupper i det hyaline Bindevæv leirede 
Celler, hvori indeholdes et yderst finkornet, grønligt Pig- 
ment, for egne Pigmentceller, der vel i den ydre Hud ere 
bundne til det hyaline Bindevæv; men som vi senere skulle 
se træffes baade i fibrillært Bindevæv og 1 Muskellagene, 
uden at de tilkjendegive sig som Kjertelorganer. 
Fordøielsesorganerne. 
Mundspalten, der gaar paalangs og er begrændset af 
tykke muskuløse Læber, fører ind til en sækformig Udvid- 
ning (Mundhulheden), som er 9”” lang og omtrent 107” i 
Gjennemsnit paa det Videste; men smalner saa stærkt af, 
at der, hvor den gaar over i Svælget, er den kun 37”. 
Denne Mundhulhed dannes af en rørformig Forlængelse af 
den ydre Hud, og paa dens indre Flade sees: flere stærkt 
fremragende, temmelig brede, circulere Folder, der dog ere 
mest fremspringende paa Rygfladen, og hvoraf de to nær- 
mest Mundspalten ere" de betydeligste. De aftage noget 
imod Svælget. 
Mundhulhedens Vægge bestaa af de samme Vey, 
som Huden. Paa den indre foldede Flade iagttages et 
tykt Lag Cylinderepithel (sandsynligvis flimrende), der rager 
ind 1 Hulheden, og er især tykt paa de fremragende Fol- 
der, som dannes af fortykket Bindevæv; udenfor Bpithel- 
laget er et temmelig bredt fibrillært Bindevævslag, hvor 
Fibrene anastomosere med hverandre, og hvori er leiret, 
dels enkeltvis, dels spredte Grupper af de samme Geller 
og Pigmenthobe, som findes i den ydre Hud, kun i en rige- 
ligere Mængde. Dette Bindevævslag støder umiddelbart til 
Muskellaget, der bestaar af Ring-, Længde- og Skraamusk- 
ler, og 1 disse Lag sees ogsaa de nysnævnte Celler og Pig- 
menthobe, men sparsommere.’ Skraamuskellaget er beklædt 
af Peritoneum. 
Hele Mundhulhedens ydre Flade er ved en Mængde 
'stærke Bindevævstraade, hvortil enkelte Muskelfibre foie 
sig, bunden til den forreste Del af Kropsvæggen. Der, 
hvor Mundhulheden gaar over i Svælget, er paa den ydre 
Flade en meget stærk Indsnøring, og paa den tilsvarende 
indre Flade er der en bred Fold, der rager cirkelformig 
ind i Hulheden og danner en Slags Sphincter, idet den er 
forsynet med stærke Ringmuskelfibre. Folden dannes af 
fortykket Bindeviey. 
' 
* Dr. J. W. Spengel har fundet et Skraamuskellag overalt i Hu- 
den hos Bonellia viridis. Mittheilungen aus der zoologischen Station 
zu Neapel, ite B. 3te Heft, 1879. 
that on the anterior portion of the body, oblique museles 
adjoin the annular and longitudinal layers.! 
Meanwhile, Schmarda’s observations differ materially 
from the results of our own examination; for neither did 
we remark any fibrillous connective tissue interlaced with 
vessels, nor any description of glandular organs. The: 
cells scattered throughout the hyaline tissue, whether 
isolated or in groups, we are disposed to regard as special 
pigmentary cells (they contain a minutely granulous, green- 
ish pigment), webbed indeed, in the outer skin, to the 
hyaline connective tissue, but which, as will afterwards 
appear, are met with alike im the fibrillous tissue and in 
the muscular layers, though not as glandulous organs. 
Digestive Organs. 
The buccal cleft, extending lengthwise, and margined 
by thick muscular labiæ, passes into a sac-like expansion (the 
buccal cavity), 9”” long and about 10”” in diameter where 
it is thickest, but narrowing so rapidly as to measure only 
37” in diameter at the gullet.. This buccal cavity is 
the result of a tubular elongation of the outer integument; 
and on its inner surface occur several broad, circular, ex- 
ceedingly prominent folds, most protuberant on the dorsal 
surface, the two in immediate proximity to the buccal cleft 
being the largest. These folds become less salient in the 
vicinity of the gullet. 
The walls of the buccal cavity consist of the same 
as that in the skin. On the inner, folded sur- 
face, is seen a thick layer of cylindric epithelium (pro- 
bably furnished with vibratile cilia), which extends into the 
cavity, and is thickest on the prominent folds, consisting 
of inspissated connective tissue. Above the epithelial layer 
lies a broadish layer of fibrillous connective tissue, with 
anastomosing fibres, throughout which are dispersed, isol- 
ated and in scattered groups, cells and amorphous lumps 
of pigment, similar to those in the outer skin, only in 
greater abundance. This layer of connective tissue directly 
adjoms the muscular integument, which is built up of an- 
nular, longitudinal, and oblique muscles; and these layers, 
too, are furnished with the aforesaid cells and pigmentary 
lumps, but more sparingly. ‘The oblique muscular layer is 
invested with a peritoneal tunic. | 
The entire outer surface of the buceal cavity is webbed 
by numbers of strong filaments of connective tissue and a few 
muscular fibres to the anterior portion of the wall of the 
body. At the commencement of the gullet, is seen on 
the outer surface of the buccal cavity a very deep instric- 
tion, and on the inner surface occurs a broad fold, pro- 
jecting with a circular sweep into the cavity, where it 
forms a kind of sphincter, being furnished with strong 
annular muscular fibres, The fold consists of incrassated 
connective tissue. 
tissue 
1 Dr. J. W. Spengel has invariably observed a layer of oblique 
muscles in the skin of Bonellia viridis. Mittheilungen aus der zoolo- 
gischen Station zu Neapel, ite B. 3te Heft, 1879. 
